Mr Zardari may try to form a coalition in Punjab, correspondents say
Pakistan's government has asked the Supreme Court to review a ruling that bans former PM Nawaz Sharif and his brother from holding elected office.
The ban on Nawaz and Shahbaz Sharif had added to recent political turmoil.
Their Pakistan Muslim League-Nawaz (PML-N) party had joined forces with lawyers to demand the reinstatement of sacked chief justice Iftikhar Chaudhry.
The protest ended when the government agreed to restore the judge and to look again at the ruling on the Sharifs.
The Supreme Court had upheld a lower court ruling banning the Sharifs. That meant Shahbaz Sharif had to step down as chief minister of Punjab province - a PML-N stronghold.
The government then imposed federal rule.
"We have requested the court to review the order in the interest of constitutionalism and the rule of law," Attorney General Latif Khosa said, adding that the government hoped the court would begin its review on Friday.
Iftikhar Chaudhry celebrated with his allies in Islamabad on Monday
Correspondents say this move - coupled with the decision over the weekend to reinstate Mr Chaudhry - is a big step towards dispelling mistrust between Pakistan's two biggest parties, which have a record of fierce rivalry.
A "long march" protest organised by lawyers and the PML-N was called off after President Asi Ali Zardari of the Pakistan People's Party backed down over the sacking of Mr Chaudhry and other judges ousted by former President Pervez Musharraf.
The judges were dismissed in 2007. Most were reinstated but not Mr Chaudhry. One reason was thought to be that he had challenged an amnesty given by Mr Musharraf that enabled Mr Zardari to return to Pakistan ahead of 2008 elections.
The "long march" had led to the detention of opposition activists and leaders, and bans on demonstrations.
The government U-turn defused what could have been a dangerous political confrontation, correspondents said.
Iftikhar Chaudhry is due to resume his post on Sunday.
However, there remains uncertainty over the continuing direct rule in Punjab.
The central government, led by the PPP, says it will lift it once a majority is established in the provincial assembly.
Correspondents say that the PPP could be angling to form a new coalition government in Punjab - at the expense of the PML-N - by allying with smaller parties.