Sweden and Finland dropped decades of military non-alignment and sought the nuclear protection afforded by the US-led defence organisation in response to Russia's invasion of Ukraine last year.

Their bids won fast-track approval from all NATO members except Turkey and Hungary.

The two ultimately relented and accepted Finland into the bloc this year.

Erdogan in July lifted his objections to Sweden's membership after Stockholm took steps aimed at cracking down on Kurdish groups that Ankara views as terrorists.

But the Turkish parliament's foreign affairs committee last month delayed forwarding the application for a vote by the full chamber -- a decision that drew a stern rebuke from NATO Secretary General Jens Stoltenberg.

Erdogan gave a second strong signal Friday that parliament will only act on Sweden if the US Congress approves Turkey's requested purchase of dozens of F-16 fighter jets and spare parts.

"You say you will take steps on the F-16 issue after passing it through the Congress, but I also have a parliament," Erdogan told reporters, referring to the United States.

"If we are two allied countries in NATO, then you can do your part simultaneously, in solidarity, and our parliament will do its part. That's the thing."

- Ageing air force -

Turkey's ageing air force has suffered from Ankara's expulsion from the US-led F-35 joint strike fighter programme in 2019.

Washington took the step in retaliation for Erdogan's decision to acquire an advanced Russian missile defence system that NATO viewed as an operational security threat.

US President Joe Biden's administration has repeatedly promised to move forward with the $20-billion F-16 sale.

But its approval has met resistance from congressional leaders who voice concern about Turkey's human rights record and past standoffs with fellow NATO member Greece.

The issue has been complicated by Turkey's anger at Washington for its support for Israel in the Gaza war.

Erdogan said Friday that he had no intention of meeting with US President Joe Biden any time soon.

"A meeting with President Biden is not on our agenda. Their stance on Gaza is known to all of you," Erdogan said.

"If he calls us, we will meet with him and talk about whatever issues we need to talk about."

Sweden's foreign minister said last week that his Turkish counterpart had promised him that Ankara would approve Stockholm's membership "within weeks".

But the Turkish parliament's foreign affairs committee has still not scheduled a hearing on the bid.