WASHINGTON — Ukrainian resistance to invading forces is stiffer than Russia expected, as the U.S. and NATO continue to supply security assistance to Ukraine, a senior defense official said.

"We continue to believe, based on what we've observed, that this resistance is greater than what the Russians expected. And we have indications that the Russians are increasingly frustrated by their lack of momentum over the last 24 hours, particularly in the north parts of Ukraine," that official said.

A paratrooper assigned to the Troop B, 5-73 Cavalry, 82nd Airborne Division trains a Polish soldier during a combined training event in Nowa Deba, Poland, Feb. 22, 2022. The 82nd Airborne Division is currently deployed to Poland to train with and operate alongside our Polish allies. The training allows allies to get to know each other’s equipment, capabilities and tactics to enhance readiness and strengthen the NATO alliance.
A paratrooper assigned to the Troop B, 5-73 Cavalry, 82nd Airborne Division trains a Polish soldier during a combined training event in Nowa Deba, Poland, Feb. 22, 2022. The 82nd Airborne Division is currently deployed to Poland to train with and operate alongside our Polish allies. The training allows allies to get to know each other’s equipment, capabilities and tactics to enhance readiness and strengthen the NATO alliance. (Photo Credit: U.S. Army photo by Master Sgt. Alexander Burnett) VIEW ORIGINAL

Ukrainian air defenses, including aircraft, continue to be operable and continue to engage and deny access to Russian aircraft in places over the country, the official said.

"As of this morning, we have no indication that the Russian military has taken control over any cities, and we still believe that Russia has yet to achieve air superiority," the official said.

The Russian invasion of Ukraine over the last 24 hours has been observed to occur over three main axes: from the south — including an amphibious assault from the Sea of Azov; from the north central; and from the northeast, a senior defense official said.

Over the last 24 hours or so, the U.S. has continued to observe more than 250 Russian missile launches, mostly short-range ballistic missiles, the official said.

U.S. Air Force Gen. Tod D. Wolters, commander of the U.S. European Command, greets U.S. Army Maj. Gen. Christopher T. Donahue, commander of the 82nd Airborne Division, in Rzeszow, Poland, Feb. 10, 2022. The 82nd Airborne Division deployed to support the U.S. European Command and assure regional allies and partners and deter any future aggression.
U.S. Air Force Gen. Tod D. Wolters, commander of the U.S. European Command, greets U.S. Army Maj. Gen. Christopher T. Donahue, commander of the 82nd Airborne Division, in Rzeszow, Poland, Feb. 10, 2022. The 82nd Airborne Division deployed to support the U.S. European Command and assure regional allies and partners and deter any future aggression. (Photo Credit: U.S. Army photo by Sgt. Catessa Palone) VIEW ORIGINAL

"We continue to see civilian infrastructure and residential areas impacted and damaged by these missile strikes," the official said, adding that it's not clear if those strikes were intentional.

Altogether, Russia has more than 150,000 troops arrayed against Ukraine, with more than 50% inside the country — up from one-third over the last 24 hours — and the rest are still along the border, the official said. There are also some Russian reconnaissance forces inside Kyiv, Ukraine's capital city.

Also, there are an increasing number of Ukrainians leaving the country, the official said, adding that the lines are stacking up on the Ukrainian side of the border with Poland.

Yesterday, President Joe Biden authorized an additional $350 million of military assistance from Defense Department inventories — including anti-armor, small arms, various munitions, body armor and related equipment — to support Ukraine's frontline defenders, who are facing down Russia's unprovoked attack, Pentagon Press Secretary John F. Kirby said Saturday.

Soldiers assigned to 5th Battalion, 4th Air Defense Artillery Regiment, line up a military vehicle during exercise Saber Strike 22 at Bemowo Piskie Training Area, Poland, Feb. 25, 2022.
Soldiers assigned to 5th Battalion, 4th Air Defense Artillery Regiment, line up a military vehicle during exercise Saber Strike 22 at Bemowo Piskie Training Area, Poland, Feb. 25, 2022. (Photo Credit: U.S. Army photo by Spc. Olivia Gum) VIEW ORIGINAL

That brings the total U.S. security assistance approved for Ukraine to $1 billion over the past year. It's the third time Biden has expedited emergency security assistance for Ukraine's defense in recent months using his presidential authority, Kirby said.

"We, along with our allies and partners, are standing together to continue to expedite security assistance to Ukraine and are employing all available security cooperation tools in support of the Ukrainian people as they defend themselves against this aggression," Kirby said.

"Our commitment and deliveries continue as a sign of our unwavering support for Ukraine sovereignty and territorial integrity," he added.

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