ISLAMABAD -- Fears mounted among opposition parties Tuesday that President Pervez Musharraf would delay the scheduled convening of Pakistan's new Parliament, after Islamists and secularists joined forces against him.

The government announced last weekend that it would summon the Lower House on Friday, to set in process a partial transfer of power from Musharraf's military regime to the first civilian government in three years.

Under controversial constitutional changes by the army chief turned president, the Parliament would be under the thumb of Musharraf and other military chiefs who would be empowered, through a planned National Security Council, to dissolve it.

However, the Parliament's inauguration has not been officially notified in the government gazette, and no member-elect has received official notification or invitation, AFP reported.

"The session is not being held because we have neither received any invitation nor has it been notified by the government," the Islamists' candidate for prime minister, Maulana Fazlur Rehman, told reporters.

Deposed premier Nawaz Sharif's party expressed alarm at the lack of notification, which is normally given at least four days before Parliament sits.

"We are very worried. It definitely seems there is going to be some delay," said Tehmina Daultana, a member-elect from the Pakistan Muslim League-Nawaz (PML-N). "The country's going through a very critical situation and it's at a standstill. Everybody's waiting for the session to be convened and the government to be formed."

The PML-N is a key member of the opposition alliance for the restoration of democracy, which struck a deal with the Islamic Party Alliance Monday to back a joint candidate to lead the future government and curtail Musharraf's powers. ARD Chief Nawabzada Nasrullah Khan said any delay would be "aimed at prolonging the military rule."

"The government, after seeing that their parties cannot form the majority, are trying to delay the calling of National Assembly session.

"This drama is being maneuvered because ... Musharraf cannot get parliamentary endorsement of changes he has made in the Constitution."

The Islamist-secular alliance has vowed to undo constitutional changes which give Musharraf sweeping powers over any Parliament and cement the military's role in politics.

The anti-Musharraf alliance and political pundits say they have a comfortable grasp of the 172-seat majority needed to form government.

The alliance has pledged to back joint candidates for the posts of prime minister and parliamentary speaker, but has yet to officially name them.

Alliance members have said privately that the fundamentalist cleric Maulana Fazlur Rehman has been agreed on, but some officials of ex-premier Benazir Bhutto's Pakistan People's Party (PPP) -- a key ard member -- indicated they were leaving the door open for their party to win the premiership.

PPP acting Secretary General, Raza Rabbani, told AFP the final announcement could be delayed until Thursday.

"I really don't think it will be announced today," he said.