The US says it does not support Ukraine's attacks on Russian territory

The United States has made it clear to Ukrainians that it does not support attacks on Russian territory, a White House spokesman said.

"The Biden administration has made it clear to the Ukrainians, both privately and publicly, that we do not support attacks on Russian territory," John Kirby, the White House National Security Council's strategic communications coordinator, told CNN after a series of drone attacks in Moscow and the region.

"We're going to continue to provide them with what they need to protect themselves and to protect their territory, Ukrainian soil, but we do not support attacks on Russia," Kirby said.

"We agree that Ukrainians have a right to self-defense – we've done very little over the last 15 months other than help them defend themselves and defend their territory from this Russian aggression. We have said that we do not want to encourage or facilitate attacks inside Russia because we do not want to see the war escalate beyond the violence that the Ukrainian people have already suffered."

Kirby did not say, however, that the US has concluded that Ukraine is behind the drone attacks.

Ukraine has denied any involvement in Tuesday's attack in Moscow, although the President's Office has made it clear that Russia has felt the consequences of its own actions after months of bombing Ukrainian cities.

"Of course, we are pleased to observe and predict an increase in attacks," said Mykhailo Podolyak, an adviser to the Ukrainian president. "But, of course, we have nothing to do with it."

Kirby reiterated on Wednesday that Ukrainian officials have assured the United States that they will not use U.S.-provided weapons to strike Russia.

"I think we can all understand that if we give Putin what he claims – that this is a war against the West, a war against the United States, a war against NATO – there will be much more suffering on the European continent, so we don't want to see an escalation of this war," he said.

"Now, look, as soon as we provide the Ukrainians with the systems, and this is an important point, they decide what they are going to do with them. They have given us guarantees that they will not use our weapons to strike Russia. But as soon as the weapons arrive, they belong to them."