Sen. Mike Rounds also expressed frustration that the United States hadn’t given Ukraine more weapons to win the war.

While the incoming Trump administration appears determined to end U.S. support for Ukraine, other western allies — including Canada — say they're not ready to give in. But can they fill the vacuum if America decides to cut and run?

Tit-for-tat moves this week included the use of American-made ballistic missiles to strike inside Russia, and new nuclear threats from Moscow. Neither appear to have influenced the war on the ground.

President Vladimir Putin said on Friday that Russia would keep testing its new Oreshnik hypersonic missile in combat and had a stock ready for use. Putin was speaking a day after Russia fired the new intermediate-range weapon into Ukraine for the first time,

The attack with an intermediate-range ballistic missile has spurred fears of a major escalation in the ongoing war and prompted Ukraine to request new air defenses.