Reuters journalist Wa Lone, center, talks to journalists during he is escorted by polices as they leave the court Monday, Sept. 3, 2018, in Yangon, Myanmar. A Myanmar court sentenced two Reuters journalists, Wa Lone and Kyaw Soe Oo, to seven years in prison Monday for illegal possession of official documents, a ruling that comes as international criticism mounts over the military's alleged human rights abuses against Rohingya Muslims. (AP Photo/Thein Zaw)

Britain called for the "immediate" release of two Reuters journalists jailed in Myanmar on Monday, saying the verdict had "undermined freedom of the media".

"We are extremely disappointed with this verdict and sentencing and we call for the journalists to be released immediately," said a spokesman for Prime Minister Theresa May.

Wa Lone, 32, and Kyaw Soe Oo, 28, are accused of breaching Myanmar's state secrets law while reporting on a massacre of Rohingya Muslims and were jailed for seven years, fuelling international outrage.

Mark Field, Britain's Minister for Asia and the Pacific, "said he was "extremely disappointed" by the verdict, calling it a "bad day" for Myanmar.

"They provided valuable reporting on abhorrent human rights violations in Rakhine state, and I have consistently called for their immediate release, including directly with the Burmese government," he said in a statement.

"Journalists must be free to carry out their jobs without fear or intimidation," he added.