Burma's parliament opens today amid a boycott by the party of pro-democracy leader Aung San Suu Kyi because of a dispute over the oath of office for MPs.
The National League for Democracy want to swear to "respect", rather than "safeguard" the constitution, which they say is undemocratic.
The dispute comes as European Union diplomats meet to decide whether to suspend sanctions against Burma.
The 1 April by-elections saw Suu Kyi and 42 NLD members elected as MPs.
The constitution was drawn up by Burma's former military rulers who reserve 25% of all seats in parliament for the military.
Aung San Suu Kyi wants, ultimately, to change the constitution because it enshrines the role of the armed forces in politics.