This combination of file pictures created on August 11, 2018 shows (L)President of Turkey and Leader of the Justice and Development Party (AKP), Recep Tayyip Erdogan deliverling a speech during an AK party's group meeting at the AK Party's headquarters in Ankara, on January 26, 2018. (Xinhua/AFP PHOTO)

WASHINGTON, Aug. 16 (Xinhua) -- U.S. Treasury Secretary Steven Mnuchin said on Thursday that the United States would slap more sanctions on Turkey if a detained American pastor was not released.

Speaking at a Cabinet meeting of President Donald Trump, Mnuchin said, "We have put sanctions on several of their cabinet members" and "we have more that we are planning to do if they don't release him quickly," referring to Andrew Brunson.

Trump also said regarding Turkey that "they have not proven to be a good friend" to the United States.

Earlier on Wednesday, White House spokesperson Sarah Sanders said the U.S. side would consider lifting sanctions that have been placed on Turkey if Ankara released Brunson and other detained U.S. citizens.

Brunson, a 50-year-old Christian pastor, was detained two years ago in Turkey on spying charges, and faces up to 35 years in prison if found guilty.

He was indicted on charges of having links with the outlawed Kurdistan Workers' Party and the Fethullahist Terrorist Organization, which Turkey accuses of being behind a coup attempt in 2016 to topple Turkish President Recep Tayyip Erdogan.

The U.S. Department of the Treasury on Aug. 1 slapped sanctions on Turkey's justice and interior ministers, citing their roles in the detention of a U.S. pastor.