By Jarrett Renshaw

RZESZOW (Reuters) –U.S. President Joe Biden landed Friday in Rzeszow to see first-hand the international effort to assist some of the million of Ukrainian refugees fleeing conflict in Ukraine. He also spoke to American troops supporting NATO’s eastern flank.

First, he met soldiers of the 82nd Airborne Division U.S. Army stationed near Rzeszow as part NATO’s protection of its eastern flank. He was seen eating pizza while chatting to several military personnel.

Biden was delayed by the delay in his schedule after Andrzej Duba, Polish president, was diverted on its way to Rzeszow. He made an emergency landing at Warsaw. Duda then boarded an alternative aircraft, and headed for eastern Poland. According to his office, Duda wasn’t in any danger.

Biden would be briefed on humanitarian responses to assist civilians in Ukraine who are under attack from Russia and the response to growing numbers of people fleeing Ukraine.

Biden said Thursday to journalists in Brussels that he will be “reinforcing my commitment for the United States to make sure they are a significant piece of dealing avec the relocation of all these people, as well humanitarian assistance needed inside Ukraine.”

Biden would travel in the evening to Warsaw to meet with Duda. The White House said that he would give a major address on Saturday.

Poland hopes Biden’s visit to Poland will highlight the United States’ security assurances that it will “every inch” of NATO territory. Warsaw would like to see additional U.S. troops on NATO’s east flank.

Poland may also bring up the idea for an international peacekeeping operation involving Ukrainian troops. It was an idea that Jaroslawkaczynski (the ruling party leader) first brought up during a visit to Kyiv.

Jake Sullivan, the national security advisor briefed journalists while he was on Air Force One traveling to Poland. Asked if Russia could bomb supplies convoys heading to Ukraine by air force one, Jake Sullivan answered: “We’re doing contingency preparation for the possibility of Russia striking NATO territory in that or any other situation.”

Sullivan stated that the President has made it clear about his determination to act decisively alongside other alliance members in the event of a Russian attack on NATO.

He said that America and its allies might still be able to take new sanctions against Russia because of its invasion in Ukraine.

He said, “Ofcourse, there are other measures to tighten sanctions and we will continue reviewing them.”

Moscow refers to its actions against Ukraine as “special military operations” in order to dearm the neighbor. Kyiv, along with its Western allies, calls it an unprovoked military operation to disarm Ukraine. They claim Russia was trying to take down the government of President Vladimir Putin’s illegitimate country.