Washington continues to engage with parties to revive the Iran nuclear agreement - the Joint Comprehensive Plan of Action (JCPOA) - and believes that Moscow shares a common interest in preventing Iran from acquiring nuclear weapons, according to White House spokesperson Jen Psaki. 

"[O]ur team, we're continuing to engage with Iran deal partners including Russia on Iran nuclear negotiations, we believe Russia shares a common interest in ensuring Iran never acquires a nuclear weapon," Psaki said during a press briefing.

Read more: Blinken: New Russia demands on Iran nuclear deal 'irrelevant'

Lloyd Austin, the US Secretary of Defense, Mark Milley, the Joint Chief of Staff Chairman and other senior officials are consulting Ukraine and NATO members regarding Poland's proposal to send MiG-29 fighters to Kiev, Psaki said.

Earlier today, regarding Poland's plans to transfer its fleet of MiG-29 fighter jets to Ukraine in exchange for US fighters, Grant Shapps, the British minister of transport, said his country has nothing to do with it and warned that NATO should be cautious about Britain's involvement in the conflict between Moscow and Kiev.

"It's nothing to do with the British government, this is between the Polish and the Americans," Shapps told Sky News broadcaster, adding that "the Americans have said that they will not proceed in that manner." 

Psaki continued, "Secretary Austin, Chairman Milley and members of our defense department are in touch with Ukrainian counterparts NATO counterparts, discussing what are clearly logistical challenges here."

Should Russia seize assets of Western companies leaving the country, Washington will respond, Psaki said. 

Read more: Ukraine parliament approves seizure of Russian assets

"[On] the potential seizing of private sector assets in Russia... if they were to take those actions, I'm certain there would be steps we would take. But nothing has happened at this point in time," Psaki said.