Eleven Pakistani MPs have reportedly joined the main parties opposed to President Pervez Musharraf that could form a coalition government.
The PPP of late former PM Benazir Bhutto fared well in the polls
Seven independent MPs joined the Pakistan People's Party (PPP) while four MPs joined its ally, the PML-N, the election commission said.
Final figures for last month's polls show the coalition lacks the majority needed to impeach Mr Musharraf.
Pakistan's army chief has urged the president and coalition to co-operate.
Gen Ashfaq Kayani also said the army would "stay out of the political process".
He told a meeting of top commanders on Thursday that the powerful military "fully stands behind the democratic process and is committed to... support the elected government".
International pressure forced President Musharraf to give up his dual role as army chief to Gen Kayani last year.
February's parliamentary elections - regarded as a key step in Pakistan's transition from military to civilian rule - delivered a crushing defeat to parties loyal to President Musharraf.
Threat to Musharraf
The election commission on Thursday night finalised its tally from the election, announcing the results for 331 of the 342 seats in the national assembly.
Militants have been attacking the military with suicide bombs
The commission also completed its proportional allocation of seats to women and minorities.
The 11 seats that have yet to be declared are subject to legal challenges and other delays.
Final figures released by the commission show the PPP of assassinated former PM Benazir Bhutto has 120 seats, making it the largest party in parliament.
The PML-N, or Pakistan Muslim League-Nawaz, led by another former PM, Nawaz Sharif, is second with 90 seats.
The proposed coalition of the two parties and their smaller allies would still lack the two-thirds majority required should they wish to impeach President Musharraf.
However, they command enough support to undermine his authority in parliament.
Coalition leaders have threatened to curtail the president's powers, though it is unclear how far they will go.
Mr Musharraf was re-elected as president last year in a parliamentary vote boycotted by the opposition as unconstitutional.
Speaking on Friday, the president said he would back any future government, as long as it did not provoke unrest.
"Durable, stable governments should be formed in the centre and provinces for five years, and if peace is maintained, I assure that I will fully support the coalition that is being formed," Mr Musharraf told Reuters news agency.
The PPP has yet to name its candidate for prime minister, though the post is expected to go to Makhdoom Amin Fahim, a party stalwart.
Ms Bhutto's widower, Asif Ali Zardari, is ineligible to run for PM but he retains great influence as party leader.
Ms Bhutto was assassinated in a gun and bomb attack in the city of Rawalpindi in December.
The new government's most pressing concern is likely to be an Islamist insurgency that has claimed scores of lives in bomb attacks in the last week alone.
Nuclear-armed Pakistan has been a key US ally in the "war on terror" and Washington hopes the new government will continue to work with it.