The U.S. is threatening further sanctions against Turkey if it does not quickly release American pastor Andrew Brunson, who has been detained by the Turkish government for nearly two years. The diplomatic spat is also taking a toll on Turkey's currency, the lira. Turkey says Brunson has ties to political groups responsible for the 2016 attempted coup of President Recep Tayyip Erdogan. Brunson runs an evangelical church in the Turkish city of Izmir. The U.S. says the pastoris "a victim of unfair and unjust detention."Turkey has accused Brunson of espionage and having ties to the Kurdistan Workers Party and the movement led by cleric Fethullah Gulen. Brunson has denied those charges. If found guilty, he faces up to 35 years in prison.On Thursday evening, President Trump described Brunson as "our wonderful Christian pastor, who I must now ask to represent our Country as a great patriot hostage": Earlier on Thursday, Treasury Secretary Steve Mnuchin hinted at more sanctions over Brunson, saying, "We have more that we are planning to do if they don't release him quickly." The U.S. doubled its tariffs on metal imports from Turkey earlier this month. In retaliation, a Turkish court refused to release Brunson, and the Turkish government raised its tariffs on imports of American cars, alcohol and tobacco.Turkey has repeatedly criticized the U.S. for not condemning the coup attempt two years ago. Erdogan wrote in an op-ed last week for The New York Times:"The Turkish people expected the United States to unequivocally condemn the attack and express solidarity with Turkey's elected leadership. It did not. The United States reaction was far from satisfactory."The Turkish government has also complained about what it calls U.S. support for Kurdish rebel groups fighting in northern Syria, and it has condemned the U.S. refusal to extradite the Pennsylvania-based Islamic cleric Fethullah Gulen, who Turkey has accused of masterminding the 2016 coup attempt.In his op-ed, Erdogan wrote: