US President Joe Biden will speak Thursday with Ukrainian President Volodomyr Zelensky to update him on US arms shipments and congratulate him on Ukrainian Independence Day, according to the White House.
John Kirby, the communications coordinator at the National Security Council, said the US would continue to "rally the free world" and "galvanize allies and partners" to support Ukraine as the Russian invasion hits the six-month mark.
He said the phone call between Biden and Zelensky would reaffirm those commitments.
"The President's looking forward to that," Kirby said, while saying there were no travel plans to discuss for Biden to visit Kyiv. He said if a "trip makes sense," it would come under consideration.
Biden on Wednesday announced a nearly $3 billion security assistance package to Ukraine.
Warning of a potential next step in the Russian invasion, Kirby said the US has information showing Russia is preparing to hold "sham referenda" in regions of Ukraine, potentially within days.
He said an announcement could come before the end of the week. The potential regions where a referenda could occur include Kherson and Zaporizhzhia, along with Donetsk and Luhansk in eastern Ukraine.
"The United States and the international community have been very clear that any attempts at controlling Ukraine sovereign territory will not be considered legitimate," Kirby said.
He said the US expects Russia to manipulate the results of the votes and falsely claim the Ukrainian people want to join Russia.
"It will be critical to call out and counter this disinformation in real time," he said.
He said the US information shows Russian officials are concerned there would be low voter turnout in the upcoming votes.