Pakistan's Prime Minister Yousuf Raza Gilani on Friday refused to step down after his contempt of court conviction, saying only the country's parliament could remove him from office.

"There is no law to remove an elected prime minister, parliament is the supreme authority and only this parliament has the authority to remove me," he said in a defiant appearance in the lower house a day after the Supreme Court verdict.

He had faced opposition calls to quit after the court convicted him for refusing to write to authorities in Switzerland asking them to reopen a multimillion dollar graft probe into President Asif Ali Zardari.

"I am an elected prime minister, representing 180 million people. How can any body order an elected prime minister to go home?" he said.

"Only the speaker of the house, who is the custodian of this house, has the authority to decide. I am ready to quit if this parliament disqualifies me."

His lawyer said Thursday he would appeal against the conviction, which opened the way for proceedings to unseat him as a lawmaker, but Gilani insisted he had done nothing wrong.

"I have not committed a crime, I have done nothing wrong but I have protected the constitution of this country," he said.

The Zardari allegations date back to the 1990s when he and his late wife, former PM Benazir Bhutto, are accused of using Swiss bank accounts to launder about $12 million in bribes from companies seeking customs inspection contracts.

Gilani insists Zardari has full immunity as head of state, but in December 2009 the Supreme Court overturned a political amnesty that had frozen investigations into the president and other politicians.