A trial date has been set for imprisoned American Pastor Andrew Brunson, who has spent 17 months in detention in Turkey over allegations of espionage and links with a terror group.

According to World Watch Monitor, Brunson, a North Carolina native who has led a small congregation in Izmir for the past two decades, has been scheduled to appear before a Turkish criminal court on April 6 on espionage and terrorism-related charges that could land him in jail for up to 35 years.

The news of the trial schedule came after a formal indictment was released by the Izmir 2nd Criminal Court to Brunson and his lawyer.

Brunson is reportedly facing 15 years for crimes committed in the name of FETO, the group headed by U.S.-based cleric Fethullah Gulen, and the outlawed Kurdistan Workers' Party, or PKK. He is facing another 20 years for allegedly obtaining state secrets for political and military spying purposes.

The indictment reportedly accused the pastor of being involved in converting Kurds to Christianity and working to establish a Kurdish state, which is long opposed by the Turkish government.

One witness had claimed that Brunson frequently met with a local leader of the FETO network, but the pastor denied knowing or ever meeting the named individual, and contended that he had never "knowingly or willingly" met with any FETO member.

On March 13, the U.S. Commission on International Religious Freedom (USCIRF), a bipartisan federal government commission, denounced the charges against Brunson.

"USCIRF urges President Trump and others in the administration to redouble their ongoing efforts to secure Pastor Brunson's release. No stone should be left unturned in our efforts on behalf of this unjustly imprisoned American," said USCIRF Vice Chairs Sandra Jolley and Kristina Arriaga.

"We call again for his immediate release and, if this is not forthcoming, for the administration and Congress to impose targeted sanctions against those involved in this miscarriage of justice," they continued.

Some critics of the Turkish government have said that Brunson is being held in Turkey in the hopes that the U.S. would be persuaded to extradite Gulen. The U.S. State Department has said that it will never happen, but Turkish President Recep Tayyip Erdogan had hinted about a trade last year, saying "Give him (Gulen) to us, and we will try (Brunson) and return him."

In January, Erdogan stated that he would refuse to extradite any jailed "suspects" to the U.S. until Washington hands over Gulen.

That same month, the representatives of more than 20 European countries described Turkey's handling of Brunson's case as "blackmail."