Ahead of the trial of the Washington Post's imprisoned Tehran bureau chief Jason Rezaian on Tuesday, the journalist's brother has announced that the proceedings would be closed to the public.

The Iranian-American Rezaian was arrested for espionage - including disseminating anti-Tehran propaganda and collaborating with hostile governments, charges the United States and the Washington Post have branded absurd.

"I think the only reason you could possibly imagine that the trial would be closed would be to prevent people from seeing the lack of evidence," Ali Rezaian said late Monday according to news agency Reuters, adding that his brother had lost 40 pounds (18 kg) since his arrest last July and subsequent stint in Tehran's notorious Evin prison.

The 39-year-old Californian was arrested along with his wife, the journalist Yeganeh Salehi (pictured above next to Rezaian), and two other Iranian-Americans. Salehi was released on bail in October.

'Shameful acts of injustice'

Martin Baron, the executive director of the Washington Post, decried the "shameful acts of injustice" being perpetrated against Rezaian, and slammed the decision not to allow the public access to the trial.

"Now we learn his trial will be closed to the world. And so it will be closed to the scrutiny it fully deserves," Baron said.

"Jason's mother, Mary, who has spent the last two weeks in Tehran awaiting the trial, will not be permitted to attend. His wife, Yeganeh, who faces related charges, will also be barred; she is to be tried separately."

Rezaian's lawyer Leila Ahsan said that the charges against her client lack any "justifiable proof" while US President Barack Obama has described them as "vague" and pressed Tehran for the journalist's release.

es/ng (AFP, Reuters)