Ukraine war: 'Frustrated' Russia could switch to 'more aggressive' tactics, US defense official warns

close

Video

Russian attack on Kyiv could be 'quite devastating': Gen. Keane

Gen. Jack Keane shares his military outlook on warfare in Eastern Europe.

Russian President Vladimir Putin has deployed nearly 75% of his assembled combat power into Ukraine, a senior U.S. defense official said Monday, as "heavy fighting" continues in different parts of the country.

The official said that Russia has not made much progress toward the capital city of Kyiv in the past day, moving roughly three miles since Sunday and remaining about 15 miles away. At the same time, Russia has so far failed to establish air superiority over the whole country.

RUSSIAN NEWS WEBSITES HACKED PURPORTEDLY BY ANONYMOUS AMID UKRAINE INVASION

"Certainly they have been slowed and they have been frustrated by their lack of progress on Kyiv," the official said, noting that this could result in a "reevaluation of their tactics and the potential for them to be more aggressive of their targeting of Kyiv."

Russian President Vladimir Putin visits the construction site of the National Space Agency on the premises of the Khrunichev State Research and Production Space Centre, in Moscow, Russia, Feb. 27, 2022. Sputnik/Sergey Guneev/Kremlin via REUTERS (Sputnik/Sergey Guneev/Kremlin via REUTERS)

When asked if it is possible that Russia may utilize air or missile strikes, the official said that "it's impossible to speculate as to how they may or may not change their plans going forward.

RUSSIA, UKRAINE MEET FOR TALKS; RUSSIA SHELLS UKRAINE'S SECOND-LARGEST CITY: UPDATES

The U.S. still believes, however, that Russia's plan is to encircle Kyiv in the coming days and that the capital city remains their "main line of effort," but "they are not there yet." Should they approach the city, the official said, Russia could use siege tactics.

The Ukrainian national flag is seen in front of a school which, according to local residents, was on fire after shelling, as Russia's invasion of Ukraine continues, in Kharkiv, Ukraine, Feb. 28, 2022.  (REUTERS/Vitaliy Gnidyi)

Russia is also aiming to take the city of Kharkiv, where there is still "heavy fighting," as well as Mariupol, in an effort to "section off" the eastern part of Ukraine, the official said.

The official had positive observations of the Ukrainian fighters, noting that "the Ukrainians are putting up continued and sustained and stiff resistance in and around Kyiv" without any signs of relenting, and have been "very creative" with their tactics.

CLICK HERE TO GET THE FOX NEWS APP

"They’re using pretty much everything that they have in their arsenal from small arms all the way up to surface-to-air missiles," the official said.

A destroyed armored vehicle is seen in front of a school which, according to local residents, was on fire after shelling, as Russia's invasion of Ukraine continues, in Kharkiv, Ukraine, Feb. 28, 2022.  (REUTERS/Vitaliy Gnidyi)

Despite the Kremlin having deployed nearly three quarters of their assembled forces, there are currently no signs that they are bringing in reinforcements just yet. The official said U.S. has not seen any indication that they are bringing in additional troops. The official also said that there is "no indication that Belarusian troops are being readied to move in Ukraine," despite reports that said it could happen.

And the U.S. has seen no specific actions from Russia after Putin raised his deterrent forces status to "special combat readiness," the official said.