A judge has called for parliament to lift the immunity of an MP with the Sunni-backed Iraqiya bloc, the deputy and a judicial spokesman said Sunday, at a time of crisis with Iraq's Shiite-led government.

Two other MPs who are opponents of Prime Minister Nuri al-Maliki also face arrest warrants and requests for their immunity to be lifted. Parliament is to vote on the three cases "soon", according to a parliamentary source.

"I received a request on Thursday to have my immunity lifted," MP Haidar al-Mullah, spokesman for the bloc, told AFP.

"I am accused of offending the judiciary and saying that the judicial system is politicised," Mullah said. "This is a new attack against Iraqiya and part of the continuous attacks against us."

Iraqiya began a boycott of parliament and the cabinet in December in protest at Maliki's alleged centralisation of power. The parliament boycott was ended last week.

It has called for Maliki to either respect a power-sharing deal or quit.

Maliki, a Shiite, has said he wants his Sunni deputy sacked after the latter said he was "worse than Saddam Hussein," while the country's Sunni vice president has been charged with running a death squad and has been hiding out in the autonomous Kurdish region of north Iraq.

Abdelsattar Birakdar, spokesman of the Higher Judicial Council, said Mullah was accused of having offended Judge Saad al-Lami in a late November interview.

Lami filed a complaint, after which a court "studied the case and then issued an arrest warrant against him and sent a request to parliament to lift his immunity in order to prosecute him," Birakdar said.

Mullah said Lami was "influenced by Maliki."

Another deputy in the case, independent MP Sabah al-Saadi said it was not the first time that he risked losing his immunity.

"Five months ago, there was a request to lift my immunity. I had been accused of offending the government, but nothing happened, and I do not know if there is a new request," he said.

"We know that the Iraqi judicial system is not completely independent, and I think that offending the government is not a crime, but rather a part of the political process," he said.

Saadi has criticised Maliki, including charging that he was acting like the late dictator Saddam Hussein.

Birakdar said his case was based on a request filed by the premier.

According to local media reports, MP Salim al-Juburi of the Iraqiya bloc also faces having his immunity lifted. He has been charged with terrorism, a charge he denies.