The American pastor Andrew Brunson yesterday denied allegations of links to a group accused of orchestrating a failed military coup in Turkey, at the beginning of a trial that will now be delayed for three weeks.

Brunson, a Christian from North Carolina who has lived in Turkey for more than two decades, was indicted on charges of helping the group that Ankara holds responsible for the failed 2016 coup against President Tayyip Erdogan. He faces up to 35 years in prison.

'I've never done something against Turkey. I love Turkey. I've been praying for Turkey for 25 years. I want truth to come out,' Brunson told the court in the western Turkish town of Aliaga, north of the Aegean city of Izmir.

The 50-year-old has been the pastor of Izmir Resurrection Church, serving a small Protestant congregation in Turkey's third largest city.

'I do not accept the charges mentioned in the indictment. I was never involved in any illegal activities,' said Brunson in fluent Turkish. His wife was in the courtroom, as were the North Carolina Senator Thom Tillis and the US ambassador for religious freedom, Sam Brownback.

At the end of the hearing, the court ruled Brunson should remain in jail as the trial continues, the pastor's lawyer told reporters. He said the next hearing will be on May 7.

Washington has called for Brunson's release while Erdogan suggested last year his fate could be linked to that of US-based Muslim cleric Fethullah Gulen, whose extradition Ankara has repeatedly sought to face charges over the coup attempt.

Gulen denies any association with the coup bid. Tens of thousands of Turks have been arrested or lost their jobs over alleged connections with the attempted coup.

'The United States cares deeply about our relationship with Turkey,' Brownback told reporters during a recess at the trial 'That relationship is going to have difficulty moving forward as long as Andrew Brunson is incarcerated.'

Brownback added: 'We completely believe Andrew Brunson is innocent...We are hopeful the judicial system will find that...You'll continue to see very high-level US government interest in this until he is released.'

Brunson's lawyer said that the pastor, who was detained 18 months ago, remained in custody because of his religious beliefs. Turkey is a majority Muslim country though constitutionally secular.

The Izmir prosecutor's office said that sufficient evidence had been obtained to charge Brunson with aiding armed terrorist organisations and obtaining confidential government information for political and military espionage.

According to Reuters, a copy of Brunson's indictment seen by the news agency accuses him of working both with Gulen's network and the Kurdistan Workers Party (PKK) militant group which has waged an insurgency in mainly Kurdish southeast Turkey and is designated a terrorist group by the US and the EU.

Additional reporting by Reuters.