Turkish president says national security adviser John Bolton ‘made a serious mistake,’ threatens new offensive against key force fighting Islamic State.

President Trump’s plans for a swift withdrawal of U.S. troops from Syria were thrown into disarray when Turkey’s president rejected a request to protect U.S. allies fighting in the region and instead threatened military strikes against them. Turkish leader Recep Tayyip Erdogan declined on Tuesday to meet with Mr. Trump’s visiting national security adviser, John Bolton, who had called on Turkey not to target a U.S.-backed Kurdish militia that Turkey calls a terrorist organization. “John Bolton made a serious mistake,” Mr. Erdogan told lawmakers from his ruling Justice & Development Party on Tuesday. “Those who share the same view are also deeply wrong.” Mr. Bolton’s inability to forge a deal with Turkey raised the possibility that a U.S. pullout could be postponed indefinitely—and it opened a new rift between two North Atlantic Treaty Organization allies who have frequently clashed over the U.S.’s Middle East policies. It also exposed weaknesses in the Trump administration’s shifting struggles to implement the president’s abrupt decision in December to quickly end the U.S.’s four-year military campaign against Islamic State in Syria.

The Trump administration began imposing new conditions for Turkey to meet before the U.S. agrees to withdraw, including a demand that Ankara pledge not to “slaughter” Kurdish fighters armed by the U.S., Secretary of State Mike Pompeo said last week. Administration officials thought Mr. Erdogan agreed to do just that in a Dec. 23 call with Mr. Trump. But the Turkish leader made it clear on Tuesday that he rejects that demand in a speech in which he personally blasted Mr. Bolton for publicly raising the demand on the eve of his visit to Ankara. Mr. Erdogan has steadfastly opposed the U.S.’s partnership with Kurdish fighters in Syria.

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