Burma's main opposition party says it will boycott parliament over a dispute regarding the constitutional oath of office, just weeks after the party won a landslide victory in the once-isolated country's by-elections.

The National League for Democracy's Executive Committee member Ohn Kyaing tells VOA's Burmese service that none of its newly elected members will attend the opening session of parliament on Monday.

The announcement comes after the Burmese government reportedly rejected the NLD's request to change the phrasing of the oath of office from “safeguarding” the country's constitution to “respecting” it.

Party officials say the issue is unlikely to be resolved in time for Monday's swearing-in ceremony, during which members were set to formally become the main opposition force in a parliament that is dominated by military-backed parties.

The NLD, which is the party of pro-democracy leader Aung San Suu Kyi, boycotted the 2010 elections that ended decades of military rule in Burma.

Since taking office a year ago, President Thein Sein has enacted a series of democratic reforms, including greater press freedom and the release of many political prisoners.

President Thein Sein was traveling Friday to Japan, becoming the first Burmese head of state to visit the country in nearly three decades.