WASHINGTON – The White House warned on Wednesday that Turkey is increasingly trending away from US interests, furious over the continued detention and trial for espionage of an American pastor there.

The Trump administration has levied tariffs against Istanbul over Turkish President Tayyip Erdogan’s refusal to release Pastor Andrew Brunson after he had given the US assurances that it would do so.

Trump had come close to negotiating his release, which included securing the release of a Turkish woman detained in Israel accused of links to Hamas. But Erdogan’s reported backtracking has infuriated the American president and prompted the expanding crisis.

In response to the latest economic punishments from Washington, Istanbul this week doubled tariffs on US imports. The move riled markets.

White House Press Secretary Sarah Huckabee Sanders said a further deterioration could be averted if Erdogan agrees to let Brunson go. The evangelical pastor was detained in October 2016 amidst a nationwide crackdown after an alleged coup shook Istanbul. He is now facing terrorism and espionage charges, which Brunson’s legal representation dismiss as absurd.

The pastor shares a lawyer, Jay Sekulow, with President Donald Trump.

Tensions between the two NATO allies have been strained for years, over policy in Syria toward the Kurdish population there and over Erdogan’s antidemocratic reforms.

The United States doubled tariffs on Turkish steel and aluminum last week, which contributed to a tumble in the Turkish lira. But a gift from Qatar on Wednesday of $15 billion in direct investment has helped buoy the currency.

“The tariffs from Turkey are certainly regrettable and a step in the wrong direction. The tariffs that the United States placed on Turkey were out of national security interest. Theirs are out of retaliation,” White House spokeswoman Sarah Sanders told reporters.

Sanders referred to Brunson as “a strong Christian who has done nothing wrong.”

Reuters contributed to this report.