WASHINGTON – The White House scrambled on Monday to repair a growing rift between the United States and Turkey after President Donald Trump threatened to "devastate" the longtime U.S. ally's economy in a Twitter post.

Trump's warning came on Sunday night in a tweet that seemed to catch even his closest advisers off-guard.

"Will devastate Turkey economically if they hit Kurds," Trump wrote on the social media site. He also suggested the U.S. would create a "20 mile safe zone" in Syria to protect the Kurds, though the president did not elaborate.

By Monday afternoon, Trump was on the phone to Turkey's president, Recep Tayyip Erdogan, while his top diplomat, Secretary of State Mike Pompeo, was struggling to explain the president's declaration.

Trump's Sunday missive came as the U.S. and Turkey are engaged in delicate negotiations over the fate of the Syrian Kurds, who have helped American military forces battle ISIS in Syria. Trump's abrupt decision last month to withdraw U.S. troops from Syria leaves the Kurds vulnerable to Turkish forces. Turkey considers the Kurdish fighters in Syria as terrorists, and Erdogan has vowed to attack them once the U.S. forces have withdrawn.

Trump's national security adviser, John Bolton, traveled to Ankara last week to seek an agreement that would protect the Kurds. But Erdogan refused to meet with Bolton and angrily denounced his entreaties.

Pompeo spoke with Turkey's foreign minister Saturday to try to quiet the diplomatic storm. In a State Department readout of that call, Pompeo said the U.S. was committed to addressing Turkey's security concerns along its border with Syria.

On Monday, Pompeo seemed at a loss to explain Trump's threat to lash Turkey's economy.

"You’d have to ask – you’d have to ask him," Pompeo said about what the president meant. "We’ve applied sanctions in many places around the world. I assume he’s speaking about those kinds of things, but you’d have to ask him."

Pompeo offered more clarity on Trump's call for a 20-mile safe zone, saying a protected area along the Turkish-Syrian border could serve to protect both the Kurds and the Turks.

"We want to make sure that the folks who fought with us to take down the caliphate in ISIS have security, and also that terrorists acting out of Syria aren’t able to attack Turkey. Those are the twin aims," Pompeo told reporters traveling with him on a swing through the Middle East. " ... Call it a buffer zone, others might have a different name for it – if we can get the space and the security arrangements right, this will be a good thing for everyone in the region," he said.

White House spokeswoman Sarah Sanders said Trump and Erdogan spoke by phone Monday, although she made no reference to the president's Twitter threat and instead echoed the more diplomatic language used by Pompeo.

"The president expressed the desire to work together to address Turkey’s security concerns in northeast Syria, while stressing the importance to the United States that Turkey does not mistreat the Kurds and other Syrian Democratic Forces with whom we have fought to defeat ISIS," Sanders said.

She said Gen. Joseph Dunford, the chairman of the Joint Chiefs of Staff, would meet with his Turkish counterpart to continue the consultations.

Bolton said the two leaders had an "excellent" talk and Trump reemphasized his commitment to protecting the Kurds.

Read more:

As Trump's timeline for Syria withdrawal slips, U.S. allies are nervous, angry, confused

US withdrawal from Syria depends on conditions, John Bolton says



