Speaking at a rare news conference for foreign media in Istanbul, Erdoğan said the United States should think very carefully before imposing sanctions on Turkey, a NATO member, and if it went ahead with sanctions, Ankara was going to retaliate.

"I say this very openly and sincerely, our relations with (President Donald) Trump are at a place that I can call really good ... In the event of any issues, we immediately work the phones," Erdoğan said.

"I do not see any possibility of these sanctions happening," Erdoğan said. But he said Turkey would not remain silent if they were imposed. "The U.S. has to think about this very carefully. We will have sanctions of our own."

He said he would discuss the issue with Trump at the G20 summit in Japan at the end of the month.

Turkey has been at loggerheads with the United States for months over Ankara's planned purchase of the Russian missile defense system, which Washington says is incompatible with NATO's defense network and could compromise its F-35 fighter jets - an aircraft Turkey is helping build and planning to buy.

The United States is threatening to impose sanctions on Turkey unless it scraps the plan to buy the Russian S-400s. Erdoğan has refused to back down. On June 20 he said deliveries are likely to start within the first half of July.

Erdoğan said while he enjoyed good ties with Trump, he could not say the same about relations between Ankara and other U.S. officials.

"When we have talks with those below Trump, we see that many cannot agree with our officials, and one example is the S-400 issue," he said.

'UN should look into the death of Morsi' 

Erdoğan also said he believed the United Nations will look into the death of former Egyptian President Mohamed Mursi and hold those responsible accountable.

Erdoğan on June 19 said Egypt's only democratically-elected President Mohamed Morsi was murdered.    

"Morsi did not die a natural death, he was killed," he said. 

Erdoğan also on vowed to pursue justice for this sudden and unexplained death.

"Turkey will do whatever it takes to prosecute Egypt [regime] in international courts," he said, in a no-holds-barred address, urging the Organization of Islamic Cooperation (OIC) to take action.

Morsi, Egypt’s first democratically-elected president, died on June 18 during a court appearance.

Security forces have been accused of murdering Morsi after friends and colleagues say police failed to administer first aid fast enough when he collapsed, according to the Independent newspaper.

Prison guards allegedly left the 67-year-old Muslim Brotherhood leader “slumped on the floor” of his courtroom cage for more than 20 minutes, despite other defendants calling for help.

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