The Australian government yesterday confirmed its foreign minister has sent a letter to her Cambodian counterpart regarding the ongoing detention of filmmaker James Ricketson on allegations of spying.

It’s the first time the Australian government has publicly acknowledged any kind of diplomatic intervention with the Cambodian authorities on Ricketson’s behalf.

“The Foreign Minister [Julie Bishop] has written to her Cambodian counterpart regarding the case of James Ricketson,” a spokesperson for the Australian Department of Foreign Affairs and Trade said in an email yesterday.

“Due to privacy obligations, and the longstanding convention of not releasing government to government correspondence, we will not provide further details.”

The news comes a day after Ricketson was questioned over a handful of emails, which his lawyer said were evidence of journalism, not “espionage”.

If convicted on the charge of collecting information that could jeopardise Cambodia’s national defence, Ricketson faces up to 10 years in prison. He has already spent eight months behind bars awaiting trial. He was arrested in June after he was seen flying a drone above an opposition rally.

Cambodian Foreign Minister Prak Sokhonn hung up on a reporter before he could be asked about the letter.

Ricketson’s family, who posted a petition directly calling for Bishop’s help, has “cautiously welcomed” her move. Their petition for Ricketson’s release has attracted some 69,000 signatures.

“Our family has been seeking high-level Australian Government assistance since my father James was imprisoned and we’re greatly relieved that finally after eight months with no assistance, Julie Bishop is taking steps to actively support us in our campaign to bring James home,” his son, Jesse Ricketson, said in a statement.

“We hope that this is the first of many steps Minister Bishop will take to support my father. We know this is not going to be an easy matter to resolve.”

“We are not experienced politicians or diplomats, we’re just regular Australians, so it’s really important that we continue to get the Australian Government to make representations on our behalf to help us get dad out of jail. We need all the help we can get.”

He added his father was a humanitarian and his arrest was a “terrible misunderstanding”, adding that there were real concerns for his health.