Stressed Relations

Mr. Brunson, who faces charges of terrorism, is under house arrest. Ankara retaliated with a similar response, imposing sanctions on two US officials whose identities have not been made public.

With an important importation Turkey of Iranian oil, analysts say it will be Washington's priority to convince Ankara to comply with its sanctions. Last month, senior US officials led by Marshal Billingslea, assistant secretary of the Treasury for Financing Terrorism, visited Ankara to meet with government ministers and business executives with the aim of putting pressure on the issue of sanctions.

Mr. Billingslea praised the talks as positive, but a confidential source described the meetings as difficult.

A source from Turkish businesses confirmed that Washington's suggestion to use Arab oil instead of Iran fails to take into account the costly price and time Turkish refinerys would need to adapt to weak quality Saudi oil.

Ankara also has strategic concerns to rely on Saudi Arabia.

“Turkey is told to buy oil from Saudi Arabia, while there is an oil pipeline with neighbouring Iran and can secure crude oil at a lower price of”, writes Ilnur Cevik, a senior adviser to the president in the Turkish newspaper Sabah. “Besides, who can guarantee that Turkey can provide sustainable oil flows at reasonable prices when Saudi Arabia occasionally displays an antagonist policy towards Ankara?”

Former US President Barack Obama made Ankara several exceptions when he imposed sanctions against Iran. Critics stress, however, that Ankara severely damaged US sanctions using gold to avoid restrictions on using dollars for trade with Iran.

Over a period Turkey was one of the largest gold importers and exporters in the world. Washington has already closed the door to use gold in trade with Tehran.

case “Halkbank”

Earlier this year, a New York court convicted a senior Halkbank official, controlled by the Turkish state, of violating US sanctions on the Iranians. The U.S. Treasury Department is considering opportunities to impose a large fine against the bank, which according to analysts may be in several billion dollars.

Analysts see Halkbank's experience as a warning to Ankara and the Turkish financial system of the dangers they faced if they violate future US sanctions.

“actually would force Ankara to choose between Iran and the United States”, said former senior Turkish diplomat Aydin Selcen, who served in Washington. “Failure to implement sanctions on Iran is not an option. There will be increased pressure from the US by creating a vicious circle in bilateral relations”.

Deep tensions between Washington and Turkey are seriously costing Turkey's financial markets. Turkish lira suffered a sharp decline last week after Washington imposed sanctions on two Turkish ministers. On Monday, the currency suffered a record drop after news of new American economic tariffs against Turkey.

American sanctions against Iran are the latest on an increasingly growing list of disputes between the two countries.

There might actually be a way out of all this” says Mr. Ozel. “But belief in these relationships has completely disappeared, and rebuilding trust in a relationship is the main and most difficult task”.