The leaders of the two parties that won the most seats in Monday's elections in Pakistan are meeting to discuss forming a coalition government.
The opposition PPP is celebrating the election result
Such a government could force President Pervez Musharraf from power.
The Pakistan People's Party leader, Benazir Bhutto's husband Asif Zardari, will have talks with Nawaz Sharif, who heads the Pakistan Muslim League.
Mr Sharif has said he wants Mr Musharraf to go, but Mr Zardari's party has been less clear-cut on the issue.
Mr Musharraf has said he wishes to stay and work towards stable democratic government in Pakistan.
He said the polls had strengthened moderate forces inside the country.
Correspondents say the most likely coalition government is between Mr Zardari and Mr Sharif's parties, as they would have more than half of parliament's seats between them.
If a new governing coalition manages to muster a two-thirds majority in parliament, it could call for Mr Musharraf to be impeached.
Mr Sharif has said he is prepared to discuss joining a coalition with Mr Zardari's party in order "to rid Pakistan of dictatorship forever".
But the BBC's Chris Morris in Islamabad says that, while a coalition between the two is the most likely option, there are certainly issues on which they disagree and there are no guarantees an alliance will emerge.
Separately, Mr Zardari has ruled himself out as prime minister, despite his party's success at the election.
He has said his PPP party would choose another candidate to lead a coalition government that opposition parties are expected to form.
Mr Zardari, a deeply divisive figure in Pakistani politics who has spent several years in prison on corruption charges, is not an MP and is therefore not currently eligible to serve as prime minister.
But there had been speculation that he might enter parliament via a by-election.
Mr Zardari has said his party could work with the MQM, a Sindh-based regional party which supports Mr Musharraf.
Mr Sharif has urged Mr Musharraf to resign, and a PPP statement cited alleged remarks by the president that he would step down if the parties supporting him were defeated in elections.
HAVE YOUR SAY
Perhaps Musharraf should leave Pakistan so that reforms can begin
In an earlier interview for the US newspaper the Wall Street Journal, Mr Musharraf said he would not resign or retire.
He was re-elected to the presidency last October, in a parliamentary vote boycotted by the opposition as unconstitutional.
He has been a major US ally in the "war on terror" but his popularity has waned at home amid accusations of authoritarianism and incompetence.
With votes counted in 258 out of 272 constituencies, the PPP has won 87 seats, according to the Election Commission of Pakistan.
The Pakistan Muslim League, or PML-N, is in second place with 67 seats so far.