Aung San Suu Kyi's party raised the prospect of a major hitch in Myanmar's political reforms Thursday, saying it may not take the seats it won in Parliament because the lawmakers' oath of office has unacceptable wording.

The National League for Democracy's platform ahead of the April 1 by-elections called for amending some sections of the constitution that the party considers undemocratic. A clause in the oath saying lawmakers have to protect and safeguard the Constitution contradicts the party's policy, NLD spokesman Nyan Win said.

The party won 43 of the 44 seats it contested, include one won by Suu Kyi herself. It would be the biggest opposition party in the military-dominated legislature that convenes April 23, and Suu Kyi, a Nobel Peace laureate and former political prisoner, would have a voice in government for the first time.

"We as citizens will abide by the Constitution but the oath says we have to protect the constitution. This is contradictory to our party policy," said Nyan Win. "To enable our elected representatives to take the oath, we need the oath of affirmation changed or we get a clearer interpretation of what it means by protecting the constitution."

The by-election's outcome was considered a major step toward reconciliation after decades of military rule in Myanmar, where President Thein Sein has undertaken political reforms since taking office a year ago.

Wooing Suu Kyi's party to rejoin politics after it boycotted the 2010 election was a key turning point in the government's campaign for Western economic sanctions imposed during military rule to be lifted.

The oath is in an appendix to the constitution, and it is unclear if it can be changed without going through the legal procedure for constitutional change, requiring the approval of 75 percent of Parliament. A court ruling might accomplish the same goal.

Suu Kyi in her 15-minute party platform presentation and other campaign speeches called for amending the 2008 constitution — which was drafted with the army's guidance — saying that its automatic allocation of 25 percent of the parliamentary seats to unelected representatives of the military is not democratic.

Win Tin, a senior NLD member, told U.S.-funded Radio Free Asia that Suu Kyi had discussed the matter with Thein Sein when they met Wednesday. It wasn't clear what step she would take regarding the oath.