Myanmar's military said Thursday it will release almost 6,000 prisoners including a former British ambassador, a Japanese journalist, and an Australian economics advisor who will be deported.

The Southeast Asian country has been in turmoil since the military coup last year.

Former British envoy Vicky Bowman, Australian economics advisor Sean Turnell, and Japanese journalist Toru Kubota "will be released to mark National Day," a senior officer told AFP.

All three would be deported, the junta said without specifying a date.

"Altogether, 5,774 prisoners including some 600 women prisoners will be released," it said, revising an earlier figure of about 700. 

Bowman, who served as ambassador from 2002 to 2006, was detained with her husband in August for failing to declare she was living at an address different from the one listed on her foreigner's registration certificate. They were later jailed for one year. Her husband will also be released, the military official said.

Ties between Myanmar and its former colonial ruler Britain have soured since the military's takeover, with the junta this year criticizing the UK's recent downgrading of its mission in the country as "unacceptable".

Sean Turnell was working as an advisor to Myanmar's civilian leader Suu Kyi when he was detained shortly after the coup in February last year.

In September, he and Suu Kyi were convicted by a junta court of breaching the official secrets act and jailed for three years each.

Kubota, 26, was detained in July near an anti-government rally in Yangon along with two Myanmar citizens and jailed for 10 years.

A source at Japan's Embassy in Myanmar told AFP they had "been informed that Mr. Kubota will be released today" by junta authorities.

Kubota would leave for Japan "today", they added.

Kubota is the fifth foreign journalist to be detained in Myanmar, after US citizens Nathan Maung and Danny Fenster, Robert Bociaga of Poland, and Yuki Kitazumi of Japan -- all of whom were later freed and deported.

According to UNESCO, at least 170 journalists have been arrested since the coup, with nearly 70 still in detention.

Three former ministers from Suu Kyi's ousted government and detained US-Myanmar citizen Kyaw Htay Oo would also be released, the junta official said.

A local monitoring group claimed that the military's crackdown on dissent since it ousted Suu Kyi's government has left more than 2,300 civilians dead.

On its part, the junta blames anti-coup militants for the deaths of almost 3,900 civilians.

Last week, UN Chief Antonio Guterres urged the Myanmar junta to immediately return to democracy, saying it was the only way to stop the "unending nightmare" engulfing the country.