Moscow ­ ­– A Russian court extended the pre-trial detention of former U.S. Marine Paul Whelan on Tuesday by three months until March 29. Whelan was arrested late last year on espionage charges and faces up to 20 years in prison if tried and convicted.

The 49-year-old Whelan, who also holds British, Irish and Canadian citizenship, was arrested in a hotel room in central Moscow at the end of December 2018.

While waiting for a ruling at the Moscow City Court on Tuesday, Whelan tried to read a statement denouncing the case against him to the press.

Get Breaking News Delivered to Your Inbox

"No espionage, no evidence, no red hand…" he said, before he was interrupted by security officers who threatened to ban reporters from the courtroom.

The rest of the statement, which Whelan displayed by pressing two pieces of paper against the walls of his glass cage, appealed to U.S. President Donald Trump and other world leaders for help. It also said that the Russian intelligence service, or FSB, was threatening him.

Russian authorities accuse Whelan of accepting a flash drive carrying classified information. Whelan says he was set up, and that he thought the drive, which was given to him by a Russian acquaintance, contained holiday photos. Whelan's family says he went to Russia to attend a friend's wedding.

Diplomats from each country Whelan is a citizen of visited him in his detention facility on Monday. Bart Gorman, the U.S. deputy chief of mission, said after the visit that Whelan was in good spirits but called on Russian authorities to grant him permission to phone his parents.

"In the past 12 months, Paul has not heard his parents' voices," Gorman told reporters outside, according to the U.S. Embassy. "Bring Paul some Christmas cheer and let him call home."

Whelan's case was brought up during Russian Foreign Minister Sergei Lavrov's recent visit to Washington, where Lavrov accused Whelan of making "all kinds of arrogant accusations."

Whelan spent 14 years in the U.S. Marine Corps before being discharged in 2008 for bad conduct. From 2017, he worked as the director of global security for Michigan-based auto parts supplier BorgWarner until the position was eliminated this month, according to Whelan's brother, David.

Whelan's defense lawyer says he expects the case to go to trial at the end of March.