As part of the deal, Erdogan said he would ask Turkey’s parliament to approve Sweden joining NATO. Hungarian Prime Minister Viktor Orban, another holdout, is expected to take a similar step.

The outcome is a victory for President Joe Biden as well, who has touted NATO’s expansion as an example of how Russia’s invasion of Ukraine has backfired on Moscow. Finland has already become the 31st member of the alliance, and Sweden is on deck to become the 32nd. Both Nordic countries were historically nonaligned until the war increased fears of Russian aggression.

Because of the deal on Sweden’s membership, “this summit is already historic before it has started,” NATO Secretary-General Jens Stoltenberg said.

Biden expressed confidence in Sweden’s path to finalizing its NATO membership as he met Tuesday with Lithuanian President Gitanas Nauseda. Biden also emphasized his commitment to transatlantic cooperation.

“Nothing happens here that doesn’t affect us,” he told Nauseda. During the meeting, Nauseda presented Biden with the Order of Vytautas the Great, the White House said. It’s the highest award a Lithuanian president can bestow and Biden is the first U.S. president to receive it.

Biden and Erdogan were scheduled to meet Tuesday evening, and it was unclear how some of the Turkish president’s other demands will be resolved. He has been seeking advanced American fighter jets and a path toward membership in the European Union. The White House has expressed support for both, but publicly insisted that the issues were not related to Sweden’s membership in NATO.

“I stand ready to work with President Erdogan and Turkey on enhancing defense and deterrence in the Euro-Atlantic area,” Biden said in a statement late Monday.

The phrasing was a nod to Biden’s commitment to help Turkey acquire new F-16 fighter jets, according to an administration official who was not authorized to comment publicly.

The Biden administration has backed Turkey’s desire to buy 40 new F-16s as well as modernization kits from the U.S. It’s a move some in Congress, most notably Senate Foreign Relations Committee Chairman Bob Menendez, D-N.J, have opposed over Turkey blocking NATO membership for Sweden, its human rights record and other concerns.