The PPP's central executive committee (CEC) during a late night meeting on Monday decided to call country-wide protests following the arrest of co-chairman and ex-president Asif Zardari.
PPP Chairperson Bilawal Bhutto Zardari in a press conference following the meeting said he would "make the government an offer".
"Bring a people-friendly budget. I will support it. We have always taken democratic steps for the people," he said.
"But you will bring a budget that is an enemy of the people (awam dushman budget)," he continued. "You are threatening my workers, my family, you arrested my father. If you bring such a budget, I will show you what a protest is," he said.
Bilawal also promised that his party would bring judicial reform and raise issues of human rights at every forum. "We are ready to take any step," he said.
The PPP has decided to set up a contact committee and run a mass contact campaign, for which a schedule and process will be determined after consensus formation and engagement with leaders, Bilawal told reporters.
He advised his party's provincial chapters' presidents to form their strategies because he would be paying them visits soon.
Well-placed sources in the PPP told DawnNewsTV it had been decided in the CEC meeting that opposition parties would participate in a multi-party conference, and that they would proceed as a joint opposition.
The sources said that the party would protest the government's "revenge tactics", the budget, and the rising cost of living.
According to the party's media cell, a protest has been called tomorrow at Karachi's Hassan Square to protest against Zardari's arrest.
Sindh Chief Minister Murad Shah appealed to party workers and supporters to maintain calm during their protest. "Threats and damage to private or public property are unacceptable," he said.
Additionally, Shah said, displaying weapons or using sticks to harass people will not be tolerated. "We will take action against this sort of behaviour."
Earlier today, former president Asif Zardari was arrested by the National Accountability Bureau in Islamabad in connection with the fake accounts case after his application seeking an extension in his pre-arrest bail was rejected.
Party leaders have written to National Assembly Speaker Asad Qaiser requesting a production order for Zardari to attend the ongoing budget session.
The former president spent 11 years in jail on corruption and murder charges before becoming president in 2008. But he was never convicted and has continued to deny any wrongdoing.
With additional reporting by Imtiaz Ali in Karachi.