Aung San Suu Kyi's National League for Democracy (NLD) said on Monday it would hold its first ever national congress on March 8-10, reflecting the dramatic political changes sweeping Myanmar.
"It will be the NLD's first nationwide conference held in democratic conditions since the party was founded (in 1988)," NLD lawmaker and party spokesman Ohn Kyaing told AFP.
Around 1,500 delegates are expected to attend, he said.
The meeting, which will define the leadership of the opposition party as it sets its sights on crucial 2015 polls, had originally been scheduled for the last week of February but was delayed.
The once-outlawed party entered parliament for the first time last year, when landmark April by-elections gave former political prisoner Suu Kyi her first ever seat in the legislature.
The hugely popular NLD is now gearing up for a general election in two years that observers say will test the limits of Myanmar's transition to democracy as it emerges from nearly half a century of military rule.
A constitutional rule currently bars Suu Kyi from becoming president because the Nobel Peace Prize winner was married to a British man and has two sons who are both foreign nationals.
At its congress, the party will elect central executive committee members, who will in turn choose a new chairperson, Ohn Kyaing said, but declined to say whether he expected Suu Kyi to be reappointed at the helm of the party.
The NLD is facing the challenge of further reinventing itself as its ageing leadership faces the growing expectations of a new generation.
The NLD swept to victory in elections in 1990 but was never allowed to take power, and Suu Kyi was detained under house arrest for much of the following two decades.
Since taking office in March 2011, however, President Thein Sein has surprised observers with rapid political changes including the release of hundreds of jailed dissidents and Suu Kyi's election to parliament.