By Ali Kucukgocmen
ISTANBUL (Reuters) - Lawyers for Metin Topuz, a U.S. consulate employee in Turkey on trial on espionage charges, applied in January to the European Court of Human Rights, a person close to the matter said on Tuesday, a day before his next court date.
The European court has accepted the application, the person said on condition of anonymity due to the sensitivity of the case. A separate application by the lawyers to Turkey's highest court was rejected in February, the person added.
Topuz's trial is one of several strains on the relationship between Washington and Ankara, NATO allies that sharply disagree over some goals in war-torn Syria and over Turkey's decision to buy Russian S-400 missile defences.
Topuz, a Turkish translator for the U.S. Drug Enforcement Administration at the consulate in Istanbul, has been in custody for nearly two years. In June a Turkish court ruled to keep him in custody at least until the next hearing, set for Wednesday.
Topuz is charged with espionage and links to the network of cleric Fethullah Gulen, who is based in the United States and blamed by Turkey for plotting the failed 2016 coup. Washington says Topuz is innocent.
He is accused of being in frequent contact with officers who led a 2013 corruption probe in Turkey, which the government has described as a "judicial coup attempt" by Gulden's network. Topuz denies the charges, saying he did not determine with whom he came into contact through his work.
The ECHR was not available for comment late on Tuesday. The court requires that all local legal methods are exhausted before it evaluates cases.
The person close to the matter said Topuz's lawyers applied early this year to Turkey's Constitutional Court. But the high court rejected the application on Feb. 7, saying it lacked a basis, given the seriousness of the charges. It has not yet ruled on a second application, the person added.
Topuz's lawyers did not respond to calls on Tuesday.
The lawyers have previously said there is a second Turkish investigation of Topuz, but they did not know details. The person familiar with the matter said this investigation could be used to keep Topuz in custody even if the ECHR rules in his favour.
"The ECHR should prioritise this case," the person said.
Topuz's arrest prompted the two countries to halt visa processes temporarily. Turkish President Tayyip Erdogan and U.S. President Donald Trump are to meet during the United Nations General Assembly in New York next week.
(Reporting by Ali Kucukgocmen; Writing by Jonathan Spicer; Editing by Dan Grebler)