A party in Malaysia’s ruling coalition said Wednesday it plans to seek a vote of no-confidence against the prime minister in an unprecedented act of rebellion that could force him to resign or call for new elections.

The Sabah Progressive Party, a member of the 14-party ruling National Front coalition, said its two federal legislators would back a motion of no-confidence against Prime Minister Abdullah Ahmad Badawi when Parliament resumes Monday.

“We have lost confidence in the prime minister of Malaysia,” party leader Yong Teck Lee told a news conference in Kota Kinabalu, the capital of Sabah state on Borneo island.

The lawmakers must first convince Parliament’s speaker to allow a no-confidence vote, but their biggest challenge will be getting enough legislators to support the motion. Prominent opposition politician Lim Kit Siang said a no-confidence motion needs a minimum 14-day notice so it can’t be voted on Monday.

The move would be a first in Malaysia’s political history: No Malaysian prime minister has ever faced a vote of no-confidence presented by a member of his own coalition before.

The National Front has 140 lawmakers in the 222-member Parliament, enough to defeat any vote against Abdullah. But after the front’s dismal performance in March 8 elections _ largely blamed on Abdullah’s leadership _ there is no guarantee that all ruling coalition lawmakers would want to protect him.

Opposition leader Anwar Ibrahim indicated that his alliance, which has 82 lawmakers, will support the no-confidence vote. At least 28 other government legislators in addition to the two Sabah members would need to support the motion to bring down Abdullah.

Several government legislators have openly voiced displeasure with Abdullah’s leadership, but it was not immediately clear if they would support the measure.

Mukhriz Mahathir, son of former Prime Minister Mahathir Mohamad and a vocal dissident, told The Associated Press that he would not back the motion if it helps the opposition take power.

If Abdullah loses a no-confidence vote, he must resign or ask the constitutional monarch to dissolve Parliament, which would pave the way for new elections. If the king refuses to dissolve Parliament, the Cabinet must resign and the king would appoint a new prime minister.

Yong’s party has long accused the National Front of neglecting Sabah’s problems, such as poverty and illegal immigrants.

He said his party would discuss whether to leave the National Front on Friday. He declined to speculate on whether it would join the opposition, but acknowledged having met with Anwar twice in recent months.

Political observers say other National Front parties may follow if Yong’s group quits.