Standing alongside Zelenskyy, Biden pledges to aid Ukraine 'as long as it takes'

In an extraordinary face-to-face meeting at the White House on Wednesday, President Joe Biden told Ukrainian President Volodymyr Zelenskyy that the U.S. "will stay with you as long as it takes" as the country enters what promises to be a brutal winter of war with Russia.

Biden pledged "unequivocal and unbending support," saying the U.S. will give Ukraine the Patriot missile battery it has requested to counter Russian missile and air attacks and much more.

Biden said he was not worried the move would escalate tensions with Russia, because "it's a defensive weapon system," designed only to shoot down incoming threats.

And he took a swipe at Russian President Vladimir Putin for targeting civilians, saying he and Zelenskyy want the war to end while Putin wants to keep it going.

“It could end today if Putin had any dignity at all, did the right thing and just pulled out," Biden said before acknowledging that that was unlikely.

"We understand in our bones that Ukraine’s fight is part of something much bigger," Biden said at a joint news conference after their meeting.

Noting that it was the fourth night of Hanukkah, Biden drew on the Jewish holiday's "story of survival and resilience" to say, "Light will always prevail over darkness."

The high-profile show of support for Ukraine comes ahead of a transition of power in Washington that will put Republicans in charge of the House of Representatives, where some GOP members have expressed reservations about the billions of dollars’ worth of arms and aid the U.S. has sent to support Ukraine’s war effort.

And it comes as Russia looks to regroup and regain the initiative after almost a year of fighting that has often disappointed Moscow. That included stepped-up attacks on Ukraine's civilian power grid, leaving millions in the cold and dark, to, as Biden put it, "use winter as a weapon."

Zelenskyy said: "We need to survive this winter. I know that American leadership will be strong. ... Regardless of the changes in the Congress, I believe there will be bipartisan and bicameral support."

Making his first trip outside Ukraine since Russia invaded 10 months ago, Zelenskyy offered Biden and the American people “all my appreciation," a message he is likely to repeat in an address to a joint meeting of Congress.

Zelenskyy, who was near the front lines in eastern Ukraine the day before his trip to Washington, gave Biden a military medal he said a Ukrainian soldier wanted him to have.

“All my appreciations from my heart, from all Ukrainians, to you, for your big support and your leadership,” Zelenskyy said, speaking in fluid but heavily accented English. “From our ordinary people to your ordinary people ... thank you so much.”

Sitting in front of a roaring fireplace with Zelenskyy, the comedian-turned-wartime leader, at his right, Biden praised him and slammed their common enemy.

“It’s an honor to be by your side in the united defense against what is a brutal, brutal war being waged by Putin,” the president said.

Ukraine is heavily reliant on U.S. and European support as it tries to fend off its far more powerful neighbor. And as the war shifts into a prolonged grinding campaign, some analysts wonder whether Washington will keep up its resolve and shipments.

Biden sought to reassure Kyiv — and warn Moscow and the world — that the U.S. was not backing down, while Zelenskyy looked to cement the partnership by taking the extraordinary risk of leaving his country to personally travel to the U.S. capital.

Zelenskyy landed at Joint Base Andrews in the Maryland suburbs of Washington, the home of Air Force One, barely more than 12 hours after the first public notice of his trip, which had been kept secret out of security concerns.

When his large motorcade of black SUVs pulled up the White House, the president and first lady Jill Biden greeted him before they headed inside.

Zelenskyy, wearing his now-familiar army-green casual attire, handed Biden the medal in a wooden display case, giving details about the soldier who he said wanted it delivered to Biden. Biden said he would get in touch with the soldier.

“Well, undeserved, but much appreciate it,” Biden responded before he called his counterpart “the man of the year” in reference to the Time magazine accolade Zelenskyy received.

Zelenskyy will meet with other administration officials before his address to Congress, where guests will not be allowed in the House gallery out of security concerns.

This article was originally published on NBCNews.com