By Aung Hla Tun
YANGON (Reuters) - Myanmar's opposition leader Aung San Suu Kyi held rare talks with President Thein Sein on Wednesday ahead of a parliament debut that her party threatened to delay unless an oath taken by lawmakers was changed.
Suu Kyi met with former junta general Thein Sein at the presidential palace in the capital Naypyitaw and discussed her new parliamentary role and "cooperating in the interests of the nation", Suu Kyi's aide, Khun Tha Myint, told Reuters.
It was the second time the 66-year-old Nobel Peace Prize winner has met the reform-minded president, who she says is trustworthy despite being a heavyweight in the authoritarian army junta that kept her in detention for 15 year.
But hours after the meeting, her National League for Democracy (NLD) party took issue with the wording of a mandatory oath taken by new members of parliament, which requires them to swear to safeguard the constitution - which Suu Kyi has pledged to amend to reduce the military's political power.
Suu Kyi won a place in the lower house when the NLD won 43 of 45 available seats in a historic April 1 by-election, thrashing Thein Sein's Union Solidarity and Development Party which is by far the dominant force in the legislature.
The NLD's 37 new lower house MPs have been invited to attend the resumption of a parliament session on April 23, but the party warned they may not.
"It is impossible for NLD elected candidates to take that oath when they join parliament," spokesman Nyan Win said.
"So our NLD candidates will not be able to attend ... but if this wording is changed before the upcoming session ends, it will pave the way for our candidates to attend parliament."
Suu Kyi carries immense political clout and her participation could boost the credibility of a fledgling parliament that is stacked with retired generals and grants a 25-percent seat quota for appointed military personnel.
The process had been going smoothly up until the NLD's announcement on Wednesday, with the international community giving tacit endorsement of the election.
Some Western countries, including Britain, France and the United States, have given strong hints they may start to lift some sanctions as early as this month in response to reforms undertaken in the year since the military dictatorship ceded power to a civilian-led administration.
(Editing by Martin Petty and Robin Pomeroy)