Opposition politicians have accused the Liberals of trying to cover up the sponsorship scandal by shutting down a parliamentary inquiry.

Conservative member of Parliament Jason Kenney says the Liberals have used their majority for weeks to limit the witness list and to control the public accounts committee's inquiry.

On Tuesday, the committee's Liberal majority voted to end the hearings and start working on an interim report.

The Liberals "used their hammer to shut down the only inquiry in town," said Kenney.

"The truth is that this represents a coverup," said Kenney. "This represents a clear effort by the prime minister to stop difficult questions from being asked days before an election about a huge Liberal scandal involving the theft of millions of tax dollars."

NDP MP Pat Martin said non-Liberal members of the committee felt muzzled and frustrated. He says there are still 90 witnesses to be heard.

"Canadians deserve to know the whole story before a general election," said Martin.

Bloc Québécois MP Michel Guimond said any report produced by the committee will be partisan and will not tell the whole story of the scandal.

Kenney has proposed that the committee sit all next week and hear from witnesses, but he expects the Liberals will vote that down.