This is CNBC's live blog covering Asia-Pacific markets.

Asia-Pacific markets fell Wednesday, with stocks in South Korea and Taiwan leading declines as major tech firms including chipmakers came under pressure after Barclays downgraded Apple.

Apple shares dropped 4% on Tuesday, after Barclays cut the iPhone maker's rating to underweight and trimmed its price target to $160 from $161. Apple suppliers in major Asia markets fell, weighing down indexes in Taiwan and South Korea.

South Korea's Kospi closed 2.34% lower at 2,607.31, while the small-cap Kosdaq fell 0.84% to end at 871.57. Most technology and chip stocks including Samsung Electronics, LG Corporation and SK Hynix fell about 3% each.

The Taiwan Weighted Index closed 1.65% lower at 17,559.31, with shares of Taiwan Semiconductor Manufacturing Company down 2.53% and Hon Hai, also known as Foxconn, falling 0.48%.

India's factory activity data from S&P Global came in below expectations for December, according to a survey by S&P Global. The purchasing managers' index for December hit an 18-month low of 54.9, compared with the 55.9 expected by economists polled by Reuters.

In Australia, the S&P/ASX 200 retreated 1.37% after hitting an all-time high{

Aussie stocks retreat from record high, down nearly 1%

Stocks in Australia were off to a weak start Wednesday, with the main S&P/ASX 200 index down nearly 1% moments after the open.

The index hit an all-time high on an intraday basis in the previous session at 7,632.70.

Australia stocks ended 2023 with gains of 7.84%, and were among Asia-Pacific markets that wrapped up the year on a positive note.

Stocks have been boosted by hopes that the Reserve Bank of Australia will no longer be hiking interest rates after the central bank held rates steady at its last meeting of 2023, partly driven by the Federal Reserve's more dovish tilt.

The Aussie dollar edged 0.06% higher on the day.

— Shreyashi Sanyal

Hong Kong's Hang Seng index fell 0.94%, while China's CSI 300 closed 0.24% lower at 3,378.30.

Japan's markets are closed until Thursday. A Japan Airlines flight collided with a coast guard aircraft at Tokyo's Haneda airport on Tuesday, causing five deaths.

The Coast Guard aircraft was headed to Niigata prefecture to provide relief for the recent earthquake that hit Japan on New Year's Day, according to initial reports.

Overnight in the U.S. the tech-heavy Nasdaq Composite dropped 1.63% and the S&P500 slid 0.57%.

Apple shares fell more than 3% after Barclays downgraded the Magnificent Seven stock to "underweight."

The Dow Jones Industrial Average managed to stay afloat as defensive stocks such as Johnson & Johnson and Merck gained.

— CNBC's Sarah Min and Alex Harring contributed to this report

Shares of Adani companies gain on news India's top court rejects probe to be transferred

Shares of Adani Group companies rose on Wednesday, after India's Supreme Court rejected a request for an investigation into the conglomerate over alleged market manipulation be transferred to another agency, Reuters reported.

Adani Energy led the rally with gains of almost 7%, followed by Adani Total Gas, up 5.83%. Adani Port, Adani Green Energy, Adani Power and Adani Wilmar jumped between 1.1% and 3.9%.

India's Securities and Exchange Board is probing the group following allegations from U.S. short-seller Hindenburg in January that Adani had improperly used tax havens and conducted stock manipulation.

India's Supreme Court also ordered the country's market regulator to complete its investigation into Adani within three months.

— Lim Hui Jie

India's factory activity expands at slowest pace in 18 months: S&P Global

India's factory activity in December expanded at its slowest rate since June 2022, according to private surveys conducted by S&P Global.

The country's manufacturing purchasing managers index came in at 54.9, lower than the 55.9 expected in a Reuters poll, and also lower compared to the 56.0 in November.

S&P Global said that's "indicative of a marked improvement in the health of the sector" and cited increases in factory orders and output, noting that input costs rose at the second-slowest pace in nearly three-and-a-half years.

— Lim Hui Jie

China online gaming stocks gain after a report says regulatory official was removed

Hong Kong-listed shares of Chinese online gaming firms rose Wednesday after Reuters reported that China removed an official at a government body that oversees the gaming sector.

Shares of Tencent rose 0.5% while NetEase added 0.68%, with China's CSI Anime Comic Game Index climbing 0.82%.

The report, citing people familiar with the matter, said Feng Shixin was removed last week from his position as head of the publishing unit of the Communist Party's Publicity Department.

The department oversees the National Press and Publication Administration (NPPA) which in turn regulates China's video games sector.

China's NPPA had published draft rules in late December that sought to prohibit incentivizing daily sign-ins for games, among other revenue-generating practices.

The country softened its stance within days of publishing the draft following a rout in gaming stocks that saw Tencent losing over $43 billion in market cap.

Video game stocks were an outlier on Wednesday, with the broader Hang Seng index down 1.27%, while China's CSI 300 index fell 0.57%.

— Shreyashi Sanyal

BYD shares fall even as its 2023 total production tops Tesla's output

Shares of Chinese automaker BYD slipped 0.76% even as the company produced more new energy vehicles compared with Tesla in 2023.

BYD manufactured more than 3 million new energy vehicles in 2023, outstripping Tesla's 1.84 million units.

While total production surpassed that of Tesla, BYD manufactured 1.6 million battery-only passenger cars and 1.4 million hybrids, putting Tesla on top for battery-only output.

Most of BYD's cars sell in a lower price range than Tesla's.

Read the full story here.

— Evelyn Cheng

Shares of Apple suppliers in Asia slide after Barclays downgrades iPhone maker

Shares of Apple suppliers in Asia tumbled on Wednesday, tracking a 4% drop in the iPhone maker overnight after Barclays downgraded the stock.

Barclays cut Apple's rating to underweight and trimmed its price target to $160 from $161.

Samsung Electronics shares slid as much as 3.01%, leading losses on South Korea's Kospi that fell 1.78%. The South Korean electronics giant, as well as some of its subsidiaries, supply Apple with its screens and battery components.

Apple chip supplier Taiwan Semiconductor Manufacturing Corp also dropped as much as 2.02%, while shares of Hon Hai Precision Industry, which assembles iPhones and is known internationally as Foxconn, fell 0.48%.

— Lim Hui Jie, Shreyashi Sanyal

CNBC Pro: Investing pro says some sectors in China have 'astonishing strength' — and names stocks to play in 2024

China's sluggish economy and property troublesturned manyinvestors bearish in 2023 — but one sees a lot of promise in certain parts of the country's market.

"The view has been, 'why would you invest in the [Chinese economy]?'… I think there's a lot of folks who are a little bearish, perhaps they think that China is on the verge of a collapse. I don't share that view," said Kingsley Jones, founder and chief investment officer at the Australia-headquartered investment firm Jevons Global.

"I think that there is a strong part of the Chinese economy; so, don't buy the Chinese economy as a whole, buy the strength," he said, naming sectors - and stocks he is bullish on.

CNBC Pro subscribers can read more here.

— Amala Balakrishner

CNBC Pro: Goldman added these stocks to its conviction list — giving them more than 50% upside

Goldman Sachs added a number of stocks to its lists of top picks, and a number of them were given significant upside.

Called the "Conviction List - Directors' Cut," the lists encompass the United States, Europe and Asia-Pacific.

Those lists are the bank's "curated and active" picks of between 15 and 30 top buy-rated stocks for each region.

CNBC Pro takes a look at five, one of which was given more than 100% upside. All price targets are for the 12 months from December 2023.

Subscribers can read more here.

— Weizhen Tan

Singapore housing sales fell to 7-year low in 2023 as private real estate market's growth declined

Singapore's private real estate market's growth declined in 2023, with annual housing sales falling to their lowest level in seven years.

The private residential price index climbed 6.7% last year, cooling from an 8.6% rise in 2022, according to data released by the Urban Redevelopment Authority.

Total sales volume in 2023 fell 15%, to the lowest level since 2016.

During the fourth quarter of 2023, the URA's private residential price index flash estimate rose 2.7% year-on-year, driven by sales of newly-launched projects. But quarter-on-quarter sales declined, with private housing sales volume falling 27%.

Singapore's government will increase housing supply in 2024, with plans to release 5,450 units in the first half of the year.

— Shreyashi Sanyal

Aussie stocks retreat from record high, down nearly 1%

Stocks in Australia were off to a weak start Wednesday, with the main S&P/ASX 200 index down nearly 1% moments after the open.

The index hit an all-time high on an intraday basis in the previous session at 7,632.70.

Australia stocks ended 2023 with gains of 7.84%, and were among Asia-Pacific markets that wrapped up the year on a positive note.

Stocks have been boosted by hopes that the Reserve Bank of Australia will no longer be hiking interest rates after the central bank held rates steady at its last meeting of 2023, partly driven by the Federal Reserve's more dovish tilt.

The Aussie dollar edged 0.06% higher on the day.

— Shreyashi Sanyal

Oil prices fall as traders monitor rising Red Sea tensions

Oil prices fell on Tuesday as traders monitored rising tensions in the Red Sea, amid a backdrop of record U.S. production and faltering demand in China.

The West Texas Intermediate contract for February lost $1.27, or 1.77%, to settle at $70.38 a barrel. The Brent contract for March shed $1.15, or 1.49%, to trade at $75.89. 

Crude prices had jumped more than 2% earlier in the trading session on escalating tensions in the Red Sea, a crucial global trade chokepoint. 

Danish shipping giant Maersk said Tuesday it will pause shipping through the Red Sea until further notice after one of its vessels came under attack by militants over the weekend.

"The market is basically saying 'we will wait and see until something happens,'" Helima Croft with RBC Capital Markets told CNBC on Tuesday. "But it's really getting much more serious every day," she said of tensions in the region.

— Spencer Kimball

S&P 500 finishes lower, with Nasdaq cinching worst day since October

After finishing 2023 with a bang, the S&P 500 finished its first trading day of the new year in the red.

The 500-stock benchmark slid 0.57% to settle at 4,742.83, while the Nasdaq Composite lost 1.63% to close at 14,765.94, notching its worst day since October.

The Dow Jones Industrial Average, however, gained 25 points, or 0.07%, to 37,715.04. It had earlier gained as much as 100 points and lost nearly 194 during the day's trading session.

— Lisa Kailai Han

Manufacturing PMI falls in December, S&P Global says

The U.S. manufacturing sector shrank more than expected in December, according to a new purchasing manager's index from S&P Global.

The Manufacturing PMI came in at 47.9 in December, down from 49.4 in November and below the 48.2 expected by economists, according to Dow Jones. A decline in new orders was one of the factors that weighed on the PMI.

"Given current order book trends, the overall picture from the survey is one of supply exceeding demand for many goods, which points to downside risks to production, employment and prices as we head into 2024," Chris Williams, chief business economist at S&P Global Market Intelligence, said in the release.

— Jesse Pound

Cyber stocks under pressure

As tech stocks slide on the first trading day of 2024, cyber security stocks are performing worse than the Nasdaq.

Several ETFs tracking the theme were down 2% or more on the day, including the iShares Cybersecurity and Tech ETF (IHAK) and the Global X Cybersecurity ETF (BUG). The First Trust Nasdaq Cybersecurity ETF (CIBR) fell 2.3%.

Some of the biggest cybersecurity stocks saw even larger declines, with Crowdstrike and Zscaler each falling more than 3%.

— Jesse Pound