Burma has revealed it owes more than $11bn in foreign debt - a figure much higher than the previous estimate.
Politicians said the finance minister had told parliament that Burma had begun talks on the debt with several countries and institutions.
Burma spent five decades under military rule and is one of the least developed countries in the world.
But the military-backed, civilian-led government that took office in 2011 has started reforms.
Finance minister Hla Tun said $8.4bn of the $11bn external debt was run up between 1962 and 1988 under the socialist administration of General Ne Win, according to MPs attending a parliamentary session in the capital Naypyidaw.
Japan was Burma's biggest creditor at that time with loans of $6.4bn, the minister was quoted as saying.
The World Bank, the Asian Development Bank and Germany were also owed several hundred million dollars each.
Since the military authorities crushed the 1988 pro-democracy uprising, Western sanctions and economic mismanagement have taken a further toll.
China has lent Burma the most in the post-1988 era, at $2.13bn, according to accounts of the minister's speech.
Analysts called it a rare disclosure, saying it was the first time for years that the Burmese authorities had made any such data public.
In 2009 Burma's national debt was estimated at $7.37bn.
The minister was quoted as saying that Burma had begun negotiations on the debt with multilateral institutions and donor countries, including Italy and Japan.
It is not clear if the government in Naypyidaw is yet repaying any of the debt.
An IMF delegation that visited Burma in January 2012 said the country could become the next economic frontier in Asia if it could turn its natural resources and young labour force to its advantage.