The Biden administration has approved the sale of F-16 fighter jets to Turkey following the Turkish government’s ratification this week of Sweden’s membership in NATO. The move is a significant development in the expansion of the alliance, which has taken on additional importance since Russia's invasion of Ukraine.

The State Department notified Congress of its approval of the $23 billion F-16 sale to Turkey, along with a companion $8.6 billion sale of advanced F-35 fighter jets to Greece, late Friday. The move came just hours after Turkey deposited its “instrument of ratification” for Sweden’s accession to NATO with Washington, which is the repository for alliance documents and after several key members of Congress lifted their objections.

The sale to Turkey includes 40 new F-16s and equipment to modernize 79 of its existing F-16 fleet. The sale to Greece includes 40 F-35 Lightning II Joint Strike Fighters and related equipment.

NATO ally Turkey has long sought to upgrade its F-16 fleet and had made its ratification of Sweden’s membership contingent on the approval of the sale of the new planes. The Biden administration had supported the sale, but several lawmakers had expressed objections due to human rights concerns.

Those objections, including from the chairman and ranking member of the Senate Foreign Relations Committee, Sens. Ben Cardin, D-Md., and Jim Risch, R-Idaho, have now been overcome, officials said.

Cardin said in statement Friday that he had still had concerns about Turkey's rights record, but had agreed to the sale based on commitments Turkey has made to improve it. “I look forward to beginning this new chapter in our relationship with Turkey, expanding the NATO alliance, and working with our global allies in standing up to ongoing Russian aggression against its peaceful neighbors,” he said.

Turkey had delayed its approval of Sweden's NATO membership for more than a year, ostensibly because it believed Sweden did not take Turkey’s national security concerns seriously enough, including its fight against Kurdish militants and other groups that Ankara considers to be security threats.

The delays had frustrated the U.S, and other NATO allies, almost all of whom had been swift to accept both Sweden and Finland into the alliance after the Nordic states dropped their longstanding military neutrality following Russia’s invasion of Ukraine in February 2022.

Sweden's formal accession to NATO now depends on Hungary, which is the last remaining NATO ally not to have approved its membership. US and NATO officials have said they expect Hungary to act quickly, especially after Turkey's decision.

White House urges Congress to approve F-16 sale to Turkey

U.S. President Joe Biden sent a letter to Congress committees on Jan. 24, saying he intends to launch the process for the sale of F-16 fighter jets to Turkey once Ankara finalizes Sweden's NATO admission process, Reuters reported, citing undisclosed sources.

The news came after Turkey's parliament voted to approve Sweden's accession to the alliance on Jan. 23, leaving the final sign-off by the Turkish president as the last remaining step. Turkey had dragged out the process of Sweden's entrance into NATO for more than a year since Stockholm initially applied in May 2022.

In a letter sent to leading Republican and Democratic members of the foreign affairs committees in both chambers of Congress, Biden asked lawmakers to approve the sale "without delay," Reuters said, citing a U.S. official.

Turkey requested to buy $20 billion worth of F-16 aircraft and nearly 80 modernization kits for its existing warplanes from the U.S. in October 2021. The Turkish Air Force currently operates around 240 F-16 fighter jets.

The finalization of the deal has been delayed as it became linked to Turkey's approval of Stockholm's entry to NATO.

Both Sweden and Finland applied to join the Alliance in May 2022 due to Russia's full-scale invasion of Ukraine. Turkey initially blocked both of their bids but gave the green light to Helsinki in March 2023.

Ankara said it had opposed Sweden's admission due to the Nordic country's alleged support for Kurdish groups that Turkey considers to be terrorists, which Sweden denies.

Turkish opposition began to weaken last July when the country's president, Recep Tayyip Erdogan, said he would forward Stockholm's bit to the Turkish parliament after Sweden had agreed to address Turkey's "legitimate security concerns."

Nevertheless, the Turkish parliament has continued to delay the ratification until earlier this week.

After Turkey, Hungary remains the last obstacle to Sweden's admission. Hungarian Prime Minister Viktor Orban told NATO Secretary General Jens Stoltenberg on Jan. 24 that Budapest supports Stockholm's entry.