UPDATE 1-Turkey stands by S-400s, says F-35 partners disapprove of U.S.

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ISTANBUL, June 24 (Reuters) - Turkey has purchased Russian missile defences and is discussing a delivery date irrespective of any U.S. sanctions, Foreign Minister Mevlut Cavusoglu said on Monday, adding the United States is isolated as it also squeezes Turkey on F-35 jets.

The Pentagon announced earlier this month that training by Turkish pilots on F-35 fighter jets had been halted at a U.S. air base in Arizona following Turkey's purchase of Russian S-400 defence systems.

The NATO allies have been at loggerheads over the issue for months. Washington says the S-400 is incompatible with NATO's defence network and could compromise its F-35 fighter jets, an aircraft Turkey is helping build and planning to buy.

Speaking at a news conference Ankara, Cavusoglu said partner nations in the F-35 jet programme do not support the steps taken by the United States to halt pilot training.

"Whatever sanctions will be decided, whatever statement would come from the United States, we have purchased S-400s and right now we are talking about when they will be delivered," Cavusoglu said.

Buying military equipment from Russia leaves Turkey vulnerable to U.S. retribution under a 2017 law known as the Countering America's Adversaries Through Sanctions Act, or CAATSA.

Turkish President Tayyip Erdogan said on Thursday that he would discuss the issue with U.S. President Donald Trump at the G20 summit in Japan this week.

(Reporting by Ezgi Erkoyun; Writing by Sarah Dadouch; Editing by Daren Butler and Jonathan Spicer)