Russia's invasion force is being slowed and frustrated by unexpectedly stiff resistance from Ukrainian troops, keeping them well outside Kyiv, a senior US defense official said Saturday.
The United States and Western allies are still able to deliver arms into the country to bolster the Ukraine military, and Washington plans to send more in the coming days to help them fight both Russian armor on the ground and assaults from the air, the official said.
According to Pentagon information, Russia now has at least 50 percent of its massive invasion force inside Ukraine.
But the force is making slow progress on its original three-front thrust due to unexpectedly stiff resistance, the official told reporters, on grounds of anonymity.
"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," the official said.
In Moscow Saturday the defense ministry said the Russian army had been ordered to broaden its offensive after Kyiv declined an offer of talks in Russia-allied Belarus.
"Today all units were given orders to develop the advance from all directions in accordance with the operation's plans," Russian army spokesman Igor Konashenkov announced.
US sending more weapons
The Pentagon believes the Russian invasion, utilizing a force of more than 150,000 troops, heavy armor, and missile and air barrages, has not progressed nearly as fast as hoped since it began just before dawn on Thursday.
As of early Saturday Washington time, the Russian military had still not taken control of any Ukraine city, nor has it gained air superiority over the country, the US official said.
"Ukrainian air defenses, including aircraft, do continue to continue to be operable and continue to engage and deny access to Russian aircraft in places over the country," the official said.
The bulk of the Russian troops remained some 30 kilometers (18 miles) outside of Kyiv, the official said, while stressing that battlefield situations were actively changing.
Ukraine's army said Saturday it had held back an assault on the capital but was fighting Russian "sabotage groups" which had infiltrated the city.
Ukrainian resistance remains "viable," and Western allies are still able to get weapons and other supplies to them despite the Russian attack, the US official said.
The Russians "have been frustrated by ... a very determined resistance and it has slowed them down."
"Based on what we've observed, that this resistance is greater than what the Russians expected," the official said.
The Russians have been more successful in the push from Crimea and the Black Sea in the south.
"But in the north, that's where the stiffest resistance is. There is still heavy fighting in and around Kharkiv," as well as north of Kyiv, the official said.
US Secretary of State Antony Blinken announced Saturday that Washington will provide $350 million in additional military equipment to Ukrainian forces.
"This package will include further lethal defensive assistance to help Ukraine address the armored, airborne, and other threats it is now facing," he said in a statement.
The US defense official said the new arms will include more Javelin portable anti-tank missiles and other items, without being specific. The official declined to answer whether they would include anti-aircraft weapons.
The United States and European allies are still able to deliver lethal weapons aid to the Ukraine military despite the Russian invasion.
"They have received security assistance from us just within the last couple of days," the official said.