Speaking in Warsaw, US vice president also supports an international investigation into possible Russian war crimes in Ukraine.
Harris told reporters at a joint news conference with Polish President Andrzej Duda in Warsaw on Thursday that US military and humanitarian assistance to Ukraine is an “ongoing process”.
“I want to be very clear: the United States and Poland are united in what we have done and are prepared to do to help Ukraine and the people of Ukraine, full stop,” she said.
Earlier this week, officials in Washington rejected the public Polish proposal to help deliver the Russian-made MiGs to Ukraine, saying that the move risked escalation with Moscow.
“Polish generosity is clearly on display for the whole world to see,” Pentagon spokesperson John Kirby said on Wednesday. “But at this time, we believe that provision of additional fighter aircraft provides little increased capabilities at high risk.”