WASHINGTON (NEXSTAR) — Speaker of the House Nancy Pelosi, D-Calif., became the highest ranking U.S. official to visit Ukraine on Sunday.

The leader led a delegation of house lawmakers to the war-stricken country, where she vowed American support.

In the surprise visit to Kyiv, Pelosi told President Volodymyr Zelenskyy that America will stand by Ukraine’s side until the end of this war. Despite typical division on Capitol Hill, lawmakers on both sides are united behind new efforts to lend more aid to the country.

During a sit-down meeting, Pelosi thanked Zelenskyy for continuing to fight for his democracy.

“Our commitment is to be there for you until the fight is done,” Pelosi said.

The visit comes as Russia aggression continues to escalate in parts of the country.

On ABC’s “This Week,” Ukraine’s ambassador to the U.S. said Pelosi’s visit speaks volumes as Ukraine continues its battle on the ground.

“We need all the assistance we can get,” Ukrainian Ambassador to the U.S. Oksana Markarova said.

At the request of the president, members of Congress are vowing to move swiftly to get more weapons and humanitarian aid to Ukraine. President Joe Biden asked Congress this week to pass a massive $33 billion aid package.

Rep. Michael McCaul, R-Texas, said it’s critical Congress acts now to ensure Ukraine has the tools to fight back as Russia tries to advance.

“Time is of the essence,” McCaul said. “The next two to three weeks are going to be very pivotal and very decisive in this war, and I don’t think we have a lot of time to waste.”

It’s unclear how fast aid can be allocated. House lawmakers are not in session next week.