Former prime minister Nawaz Sharif today pulled his party out of Pakistan's six-week-old coalition government to plunge the nation back into political uncertainty.
Mr Sharif, whose Pakistan Muslim League (Nawaz) was the second-largest member of a four-party alliance, made the announcement after failing to break a deadlock with its main coalition partner over the reinstatement of dismissed judges.
Mr Sharif had made the restoration of 60 judges sacked by President Pervez Musharraf in November the main condition for joining the coalition led by the party of Asif Ali Zardari, the widower and political successor of the late Benazir Bhutto.
Three days of talks in London between Mr Sharif and Mr Zardari, whose Pakistan People's Party (PPP) leads the coalition, ended on Sunday without any breakthrough, however.
"Our ministers will meet the prime minister tomorrow and will submit their resignations," Mr Sharif said. But he added his party would continue to support the PPP government despite quitting the cabinet.
There had been high hopes that the alliance between the two main political forces would assert civilian rule in a country that has been led by generals, like Musharraf, for more than half the time since it was founded in 1947.
If the PML-N were to withdraw support completely, analysts say the PPP could end up inviting Musharraf's allies to join the coalition, or call for another election.
Analysts say the split in the coalition would be welcomed by US ally Gen Musharraf, who came to power in a 1999 coup and only quit as army chief last November.
The humiliating loss of parliamentary support in February polls had left him isolated.