• Russian President Vladimir Putin is likely to accelerate the Kremlin's military campaign in Ukraine amid stalled progress, U.S. officials warned Tuesday.
• "I think Putin is angry and frustrated right now. He's likely to double down and try to grind down the Ukrainian military with no regard for civilian casualties," warned CIA director William Burns.

WASHINGTON – Russian President Vladimir Putin is likely to accelerate the Kremlin's military campaign in Ukraine amid stalled progress after nearly two weeks at war, U.S. officials warned Tuesday.

The intelligence chiefs, who had previously warned of Putin's invasion of Ukraine, outlined a number of issues the Russian military is currently facing on the battlefield.

"We assess Moscow underestimated the strength of Ukraine's resistance and the degree of internal military challenges we are observing which include an ill-constructed plan, morale issues and considerable logistical issues," Avril Haines, director of national intelligence, said before the House Intelligence Committee.

U.S. intelligence analysts believe those setbacks won't deter Putin, who "instead may escalate, essentially doubling down," she said.

"We assess Putin feels aggrieved the West does not give him proper deference and perceives this as a war he cannot afford to lose," added Haines, who leads America's 18 intelligence agencies.

Alongside Haines, CIA Director William Burns told lawmakers that Putin is growing increasingly frustrated that Kyiv has not yet fallen to Russian forces.

"Instead of seizing Kyiv within the first two days of the campaign, which was what his plan was premised upon, after nearly two weeks, they still have not been able to fully encircle the city," Burns said.

"I think Putin is angry and frustrated right now. He's likely to double down and try to grind down the Ukrainian military with no regard for civilian casualties," Burns warned.

The officials declined to elaborate on what specifically Putin would do next as well as provide a timeline for such moves.

The testimony provided by America's top spy chiefs complements the intelligence community's unclassified version of the annual threat assessment report. The report was compiled before Russia's invasion of Ukraine.

At the Pentagon, a senior U.S. defense official separately said Tuesday that Russian forces are pursuing four different advances on Kyiv and are approximately 12 miles from the city center.

The official, who spoke on the condition of anonymity in order to share new details of the Pentagon's assessment, said that Russian troop movements deeper into Ukraine have slowed.

"They still seem to be plagued by logistics and sustainment challenges," explained the official, adding that the Russians are facing substantial fuel and food shortages.

"We have every expectation that they will try to overcome those challenges," the person said.

The official added that almost all of the Russian forces once lined on Ukraine's borders are now in Ukraine.

"We assess that nearly, not all but nearly 100% of the forces that they had amassed are inside the country now and clearly they are inside the country with the intent to move along these multiple lines of access," the official said.

Earlier in the week, Pentagon spokesman John Kirby said that Russian force movements in Ukraine have slowed.

"The Russians continue to get frustrated and slow down and they really haven't made any noteworthy progress in the last few days," Kirby said. 

"They are having morale problems. They are having supply problems. They are having fuel problems. They're having food problems. They are meeting a very stiff and determined Ukrainian resistance," he added.