"President Zardari is no more the co-chairman of the PPP. The main body of the PPP has been dissolved and his son, Bilawal Bhutto Zardari, has been elected the party's patron-in-chief," a close aide to 57-year-old Zardari told PTI.
Earlier, Bilawal, 24, was the chairman of the PPP.
The decision was made in compliance with the Lahore High Court's order which had asked Zardari to quit his post in the PPP as the President is expected to be impartial.
The High Court has also asked the President not to indulge in political activities.
"We hope the President will get relief from the High Court after quitting his political office," said the aide to Zardari, who did not want to be named.
During the hearing of the case, Wasim Sajjad, the government's lawyer, had informed the court that the PPP was a "private organisation" and had nothing to do with politics.
Sajjad had also informed the court that the party that had headed the government was the PPP-Parliamentarians, which was registered with the Election Commission.
After appointing Bilawal the patron-in-chief, PPP leaders plan to get the party registered with the Election Commission on March 25.
The PPP-Parliamentarians had recently applied for the arrow as its symbol for the general election to be held on May 11.