(NewsNation) — Ukrainian President Volodymyr Zelenskyy on Wednesday gave U.S. President Joe Biden a medal while visiting the White House for his first known trip outside Ukraine since Russia invaded in February.

“Undeserved but much appreciated,” Biden said to Zelenskyy after being given a cross for military merit that had been passed along by a Ukrainian captain.

Speaking briefly before reporters, Biden told Zelenskyy it’s “an honor to be by your side,” while pledging to continue helping Ukraine.

The highly sensitive trip comes as U.S. lawmakers are set to vote on a year-end spending package that includes about $45 billion in emergency assistance to Ukraine. The Pentagon is also preparing to send $1.8 billion in military aid in a massive package that will include, for the first time, Patriot surface-to-air missiles.

Warning Zelenskyy that Russian President Vladimir Putin is trying to use winter as a weapon, Biden said the Ukrainians are inspiring the world with their courage, resilience and resolve.

Zelenskyy said he wanted to visit the White House sooner, but the situation was difficult.

The Associated Press contributed to this report.