Burma's military junta says it will free more than 5,000 prisoners, in addition to nearly 4,000 it said last week would be released.
Veteran Win Tin is said to be on the list to be released
State media said the new releases would take the total number of prisoners freed or set to be released to 9,248.
Very few are political prisoners, but one man reportedly due to be freed is veteran dissident Win Tin.
Analysts said the announcements were partly designed to stem criticism of Burma ahead of a regional summit.
The Association of South East Asian Nations (Asean), which is meeting in Laos, does not discuss the internal affairs of member states.
But the organisation has come under mounting international pressure over Burma, and its lack of political reform.
A BBC correspondent in Bangkok says the military junta also wants to shore up its support inside Burma, in the wake of the ousting of former prime minister Khin Nyunt last month.
Reports of the extended amnesty came as authorities resumed the mass-release programme on Thursday, after a five-day hiatus.
A small group of inmates was freed from Burma's largest jail, according to AFP.
The first release was announced last week, with the government saying it was lifting the sentences on 3,937 prisoners because they had been wrongly arrested by Burma's intelligence services.
But only several hundred were believed to have been set free before Thursday.
In an interview with Reuters news agency on Thursday, Deputy Foreign Minister Kyaw Thu denied prisoner releases were trailing off.
He said the perceived slowness was due to transporting prisoners to Rangoon for processing from all over Burma, which is also known as Myanmar.
Min Ko Naing: Freed from jail aged 42, after 15 years
The minister added that authorities would come under both internal and Western pressure if they did not keep to their word.
Kyaw Thu also confirmed that among those set to be released was high-profile dissident Win Tin.
"Win Tin is already on the list," he said.
Win Tin, 78, is a prize-winning journalist who was secretary of Burma's opposition party, the National League for Democracy (NLD) until 1989, when he was arrested on 4 July of that year on political grounds. He suffers from poor health.
He is also a close aide of democracy icon Aung San Suu Kyi.
Aung San Suu Kyi remains under house arrest and there are no signs she will be released any time soon.
"I don't know when the house arrest will be lifted," Kyaw Thu told Reuters.
Those released from prison so far include about 20 political prisoners.
One of them is dissident Min Ko Naing, who was freed on Friday after being jailed 15 years ago for leading 1988 pro-democracy student protests crushed by the military.