Myanmar, facing international outrage over the jailing of Reuters journalists for their reporting on a massacre of Rohingya Muslims, is conducting a "political campaign" against independent journalism, the UN said yesterday.

A fresh report from the UN rights office decried "the instrumentalisation of the law and of the courts by the government and military in what constitutes a political campaign against independent journalism".

It slammed the "failure of the judiciary to uphold the fair trial rights of those targeted".

UN rights chief Michelle Bachelet yesterday warned in a statement that the situation was "hardly conducive to a democratic transition" in Myanmar.

She called on authorities in the country to "cease the legal and judicial harassment of journalists and to initiate a review of ill-defined laws that facilitate attacks on the legitimate exercise of freedom of expression".

The rights office pointed to the "particularly outrageous" and high-profile example of the conviction of Reuters journalists Kyaw Soe Oo and Wa Lone.

Last week, a judge jailed the two -- both Myanmar nationals -- for seven years under a draconian state secrets act over their reporting of the Rohingya crisis.

The UN report said there were many other examples of detentions and prosecutions of journalists and their sources, indicating "wider trends of suppression of freedom of expression".

According to the report, laws on telecommunications, official secrets, unlawful association, electronic transactions, import-export and aircraft have been used against journalists in a number of cases.

In Myanmar, it has become "impossible for journalists to do their job without fear or favour," it said.