ANKARA, TURKIYE -- Ratification of Sweden's NATO membership by Turkiye's parliament hinges on the U.S. Congress' approval of Turkiye's request to purchase F-16 fighter jets, Turkish President Recep Tayyip Erdogan has said, calling on the two legislatures to act "simultaneously."

In comments reported on Tuesday, Erdogan also said Canada and other NATO allies must lift arms embargoes imposed on Turkiye.

"Positive developments from the United States regarding the F-16 issue and Canada keeping its promises will accelerate our parliament's positive view on (Sweden's membership,)" Erdogan said. "All of these are linked."

He made the comments late Monday while returning from a visit to Hungary. Hungary and Turkiye are the only two NATO members not to have formally approved Sweden's bid to join the trans-Atlantic military alliance.

Erdogan's comments were reported by the state-run Anadolu Agency.

He told reporters that Turkish Foreign Minister Hakan Fidan raised the issue of a simultaneous approval by Turkiye's parliament and Congress during discussions this week with U.S. Secretary of State Antony Blinken.

"If we operate this simultaneously, we will have the opportunity to pass this through the parliament much more easily," Erdogan quoted Fidan as telling Blinken.

Erdogan submitted a protocol on Sweden's admission to parliament in October, but the ratification process stalled.

The Turkish leader has since linked the matter to Congress approving Turkiye's request to purchase 40 F-16 fighter jets and kits to modernize its existing fleet.

Turkiye has delayed ratification of Sweden's membership for more than a year. Ankara accuses the country of not taking Turkiye's security concerns seriously enough, including its fight against Kurdish militants and other groups that Ankara considers to be security threats.

The delays have frustrated other NATO allies, who were swift to accept Sweden and Finland into the alliance after the neighbouring countries dropped their longstanding military neutrality following Russia's invasion of Ukraine in February 2022.

Hungary has said the country would not be the last to approve accession, though the ruling Fidesz party, which holds a constitutional majority in Hungary's parliament, has refused to hold a vote on the matter.