Turkish President Recep Tayyip Erdogan said Friday that Turkey may consider countries such as Russia if the US fails to follow through with a pledge to deliver F-16 fighter jets.

Turkey was stripped from a program to replace a variety of fighter, strike, and ground attack aircraft for NATO allies after acquiring a Russian missile defense system in 2019. 

However, as the US seeks rapprochement with Turkey in response to the Russian military operation in Ukraine, US President Joe Biden promised Erdogan in June that he would support the sale of less advanced F-16 jets. Because of worry among top US politicians over Turkey's aggressive rhetoric toward its old opponent Greece, this has failed to garner pace in Congress, whose backing for military sales is essential.

"The US is not the only one selling warplanes in the world. The UK, France, and Russia sell them as well," Erdogan told reporters after Friday prayers. 

"It's possible to procure them from other places, and others are sending us signals," Erdogan said.

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Erdogan has made a series of complimentary remarks about Russia ahead of a meeting with Russian President Vladimir Putin at a regional conference in Uzbekistan next week.

He accused the West of provoking Russia by supplying Ukraine with weaponry, and he blamed European sanctions for the continent's energy crisis.

Erdogan also disclosed that he had urged Putin to grant Turkey a discount on Russian natural gas imports.

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Ankara's strategic ties with Washington have been strained for years by issues ranging from Turkey's deteriorating human rights record to US occupation cooperating with Kurdish forces in Syria that Erdogan views as "terrorists".

Erdogan said he will raise US military support for the Kurdish forces if he had the opportunity to meet with Biden on the sidelines of the annual UN General Assembly meeting, which begins on September 13.