U.S. House of Representatives Speaker Nancy Pelosi has arrived in the Ukrainian capital Kyiv and met with Ukrainian President Volodymyr Zelenskyy on Sunday.

In a video released by the president's office, Zelenskyy greeted Pelosi and her delegation, and the two sides held a meeting afterwards.

"Our delegation traveled to Kyiv to send an unmistakable and resounding message to the entire world: America stands firmly with Ukraine," Pelosi said in a statement.

Her trip came after a visit last weekend to Ukraine by U.S. Secretary of State Antony Blinken and Secretary of Defense Lloyd Austin.

Pelosi said Zelenskyy had made clear that Ukraine needed more security, economic and humanitarian aid amid the crisis.

"Our delegation proudly delivered the message that additional American support is on the way," she said.

On Friday, she said she hoped to pass a $33 billion aid package for Ukraine requested by President Joe Biden as soon as possible.

Delivering remarks from the White House, Biden also proposed legislation to hold Russian oligarchs accountable for their alleged role in supporting the military operation, according to a separate factsheet by the White House detailing the proposal.

Calling the U.S. "the leader in strong support for Ukraine" in the crisis, Zelenskyy tweeted that the support helps protect the sovereignty and territorial integrity of his country.

Russian Foreign Minister Sergey Lavrov has repeatedly urged the United States and NATO to stop supplying Kyiv with arms if they are "really interested in resolving the Ukraine crisis."

"If the U.S. and NATO are really interested in resolving the Ukraine crisis, then first of all, they should wake up and stop supplying Kyiv with arms and ammunition," he said in an interview with Xinhua News Agency.

(With input from agencies)