COLOMBO: Sri Lankan lawyers have asked the Supreme Court to declare parliament's impeachment of the chief justice illegal, a legal spokesman said Tuesday, a move that could trigger a constitutional crisis.

The influential Bar Association representing the country's 11,000 lawyers has petitioned the Supreme Court to rule against the impeachment by a parliamentary panel, the spokesman for the association said.

It was the first time the main professional legal body had united to oppose the move against Shirani Bandaranayake, which has raised international concern that the government is trying to control the judiciary.

A parliamentary committee on Friday held the first day of a closed-door hearing against Bandaranayake, who has said there was not an “iota” of truth in allegations against her.

The Supreme Court has asked that the hearings be suspended pending its decision on the legality of the process.

But parliament has insisted it was supreme and could not be dictated to by the judiciary.

Ruling party legislators have also warned the Supreme Court not to interfere.

The impeachment hearing against Bandaranayake, 54, Sri Lanka's first female chief justice, is due to reconvene on Dec 4.

“It is an unconstitutional interference with the judiciary, a disregard of the rule of law, and the violation of the fundamental rights of the bar,” Bar Association head Wijedasa Rajapakse told reporters.

Rajapakse is also an opposition MP and not related to President Mahinda Rajapakse.

The Supreme Court headed by Bandaranayake irked the president last month with a decision that effectively scuppered a bill to give more powers to the economic development minister, who is the president's younger brother Basil.

Bandaranayake has been accused of failing to declare around $250,000 in foreign currency, among other alleged misdemeanours. She has denied the charges.

The government and the Supreme Court have clashed over the case. Rights groups see it as the latest attempt by President Rajapakse to tighten his grip on power after crushing Tamil militants in 2009.