U.S. and Turkish officials met Wednesday in Washington to try to resolve the crisis in relations over Turkey’s detention of Andrew Brunson, an American pastor, but neither side reported progress or gave any indication they were closer to a resolution.

Turkish Deputy Foreign Minister Sedat Onal and counterparts from his government’s Finance Ministry met for less than an hour with Deputy Secretary of State John Sullivan.

In a statement, State Department spokeswoman Heather Nauert said only that they “discussed a range of bilateral matters including Pastor Brunson.” Turkey’s embassy did not respond to a request for comment.

Brunson, a Christian pastor who has lived for two decades in Turkey, was arrested in 2016 and charged with having terrorist connections and with complicity in a failed coup attempt that year against President Recep Tayyip Erdogan. After nearly two years in prison, he was released last month to house arrest, and his trial is not scheduled to resume until October.

The case has become the primary cause of downward-spiralling relations between the two NATO allies, as President Trump and Vice President Pence have insisted Brunson is innocent and demanded his release. Last week, Trump imposed sanctions against two Turkish cabinet ministers, actions that were quickly reciprocated by Erdogan.

Both governments have indicated, however, that they want to resolve the dispute, and this week’s talks were previewed as a step in that direction.

One element of an agreement could include a prisoner swap, with Brunson’s release in exchange for the return home of Turkish banker Hakan Atilla, who was sentenced in federal court earlier this year to 32 months imprisonment for his involvement in violations of U.S. sanctions on the purchase of Iranian oil.

The sanctions, ultimately lifted as part of the Iran nuclear deal agreed to under President Barack Obama, provided for limited exemptions to some countries, including Turkey, although Atilla was convicted as part of a scheme to violate remaining restrictions.

Further complicating already difficult U.S.-Turkey relations, Trump has withdrawn U.S. participation from the Iran nuclear deal and plans in November to reimpose sanctions, including a worldwide ban on importing Iranian oil and gas products. The administration has said that no exemptions will be given.

Turkey is dependent on imports for nearly all of its energy needs, with nearly half of its crude-oil imports coming from Iran and a significant portion of its gas.

The Turkish delegation here to discuss the Brunson issue is also talking about the upcoming Iranian sanctions, Energy Minister Fatih Donmez told reporters in Ankara on Wednesday. “I think a good outcome will emerge,” he said