WASHINGTON -- A senior State Department official has lashed out at Turkey and Egypt for military deals they have struck with Russia, warning of sanctions against the U.S. allies if they don't reverse course.

The official, who briefed reporters on the condition of anonymity, on November 21 said Ankara has to "get rid of" the Russian-supplied S-400 missile defense system - which it has purchased and started to take delivery on - if it wants to improve ties with Washington.

Turkey, a NATO member, received a first batch of the missile defense systems in July, prompting the United States to kick Turkey off its F-35 fighter jet program.

U.S. and NATO military officials have long opposed Turkey's purchase of the S-400 from Russia, saying it was not compatible with alliance military systems and would endanger new F-35 jets used by the West.

The United States says Russia will be able to acquire sensitive technical details about the new U.S. warplane if it is operated alongside the S-400.

Washington has pressed Turkey to drop its buy of the Russian system and to instead purchase the U.S.-made Patriot system, but Turkish President Recep Tayyip Erdogan has refused to back down, even at the risk of sanctions.

President Donald Trump hosted Erdogan at the White House last week in a meeting that Trump called "wonderful."

But it was unclear if progress had been made on the S-400 issue, and Erdogan later said he told Trump that Turkey would not give up on the Russian system and cited strong ties with Moscow.

The State Department official, who said he was aware of Erdogan's remarks, told reporters that 'there is room for Turkey to come back to the table. They know that to make this work they need to either destroy or return or somehow get rid of the S-400.'

'They [the Turks] know that they have the choice to move forward, and the choice is to rid themselves of the S-400 so that we can move forward,' he said.

The official added that the imposition of U.S. sanctions under Countering America's Adversaries Through Sanctions Act (CAATSA) was still a possibility.

The official also said the United States is working with Egypt to deter it from proceeding with a $2 billion deal to buy more than 20 Su-35 Russian fighter jets.

The official said that "we've also been transparent with them in that if they are to acquire a significant Russian platform...that puts them at risk towards sanctions.'

'They know this and we're working through it with them,' the official said. 'This is something we've not completely reconciled yet but they're acutely aware of what they're putting at risk.'

Washington has told Cairo that using the Su-35 and other Russian weapons systems could pose a threat to a country's ability to operate jointly with U.S. and NATO militaries in the event of a crisis.

While not a NATO member, Egypt has over the years received billions of dollars in economic and military aid from the United States and is considered a long-time ally in the unstable Middle East region and its military operates the U.S.-supplied F-16 fighter jet.

With reporting by Reuters

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