SYDNEY: Australian journalist Alan Morison has been forced to shut down his crusading news website in Thailand as he and a Thai colleague face trial on serious criminal charges on Tuesday.



The award-winning Phuketwan site has led reporting on the plight of Rohingya in Myanmar, who have been described by the United Nations as among the world's most persecuted people.



Morison, 67, has announced that Phuketwan will close this week and may never resume because of uncertainty over unprecedented criminal defamation charges brought against him and colleague Chutima Sidasathian by the Royal Thai Navy.



"We feel committed to make a stance for a free media in Thailand," Morison said.



"We are content to leave the decision to Thai justice, although some people have concerns about the potential for a negative outcome," he said.



"This case was wrong from the beginning, with one or two officers acting on bad advice."



Morison, a former senior Age editor, and Chutima face up to seven years' jail on charges that relate to a single paragraph republished in Phuketwan in July 2013 from a Reuters report on Rohingya refugees.



Reuters subsequently won a Pulitzer prize for its reporting on Rohingya that included the paragraph.



But the Royal Thai Navy only laid charges over the Phuketwan republication, prompting widespread criticism that it has singled out a small independent news outlet that had broken numerous stories on the plight of the Rohingya over seven years.



Morison's Phuketwan website led reporting on people trafficking through Thailand.



Chutima had worked as a paid fixer for Reuters on its Rohingya coverage and introduced Reuters reporters to news sources.



Morison and Chutima recently sent a letter to Thai authorities expressing "deep regret" at what had transpired but insist an apology is not warranted.



"We have no intention of apologising for something that we haven't done," Morison said. "This is a matter of important principle."



Eight human rights groups, including Human Rights Watch and Amnesty, and journalist groups last week appealed to Thai Prime Minister Prayuth Chan-ocha to drop the charges, saying in a joint letter the legal action threatens the right to freedom of opinion and expression that is supposed to be the bedrock of Thailand's democratic society.



They said the use of the Computer Crime Act in the case was particularly troubling because it was the first time that one of Thailand's armed services had used it against journalists.



The Media, Entertainment and Arts Alliance (MEAA), which represents Australian journalists, and the Federation of Journalists, which represents more than 600,000 journalists worldwide, have commissioned senior Brisbane barrister Mark Plunkett to observe the trial on the resort island of Phuket that is expected to be held over three days.



A verdict is expected in about a month.



Media organisations and human rights groups say there has been a steady decline in press freedom in Thailand since the country's army, then led by Mr Prayuth, staged a coup to topple Thailand's democratically-elected government in May last year.