Taiwan's parliamentary speaker scored another victory in the battle for his job Monday after the high court upheld a ruling against his party's decision to expel him over claims of influence-peddling.

Earlier this month, the Taipei district court granted Wang Jin-pyng's request for a provisional injunction against the Kuomintang (KMT) party, allowing him to hold his party membership and therefore continue as speaker.

The party, led by President Ma Ying-jeou, appealed the ruling, but the appeal was thrown out by the high court on Monday.

"The appeal was rejected," the court's spokesman Hung Kuang-tsan told reporters.

The KMT said the party would appeal to the Supreme Court.

Wang, 72, was a KMT heavyweight known for his grassroots influence. His removal has sparked fears of a split within the party in a deepening political scandal that has already seen two top government officials, including justice minister, resign.

Ma had said Wang was "unfit" to head the legislature after he was accused of influencing prosecutors in the court case of Ker Chien-ming, the major opposition Democratic Progressive Party's (DPP) party whip in parliament.

A twist developed last week when prosecutors admitted that they had tapped lawmakers' phones while investigating Ker's case.

The prosecutors insisted the wire tapping was legal, but the DPP compared it to the Watergate scandal in the United States that resulted in the resignation of then-president Richard Nixon in 1974, and demanded Ma step down.

Pressure on Ma's administration has mounted after local workers lost their jobs following the mass shifting of assembly lines from the island to the Chinese mainland to capitalise on cheap manpower and land prices there.

His popularity has taken a severe hit in the wake of a series of scandals culminating with the accusations against Wang.

Thousands of people took to the streets of Taipei in several protests on Sunday, hurling shoes at the portrait of the beleaguered president and demanding he resign.

Ma's approval rating had hit a record low of around 9.0 percent earlier this year, before rising to more than 21 percent in a recent poll.