Ibrahim Kalin urged the United States to respect Turkey's judicial independence in a written statement to Reuters. The spokesperson noted that the US administration had made arbitrary comments and demands in Brunson’s case.

"There is rule of law in Turkey and the Andrew Brunson case is a legal issue. There is an ongoing legal process related to this individual," Kalin said, stressing that Ankara finds "unacceptable the disregard of the legal process by the United States, which has been making certain demands."

Erdogan's spokesman also remarked that the US administration most recent policies were at odds with the principles and values of NATO, saying that the recent US National Security Adviser John Bolton's comments meant that the US was targeting a NATO ally in an economic war.

Kalin’s comments came after Bolton told Reuters earlier that Turkey had made a "big mistake" in not releasing Brunson.

The Turkish currency value has been falling recently amid a diplomatic and trade row with Washington. Brunson is currently under house arrest in Turkey on charges of complicity in a failed 2016 coup.

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