Bilawal, 24, will not address any rallies or meetings ahead of the general election due to threats to his life, sources in the PPP were quoted as saying in a report on the website of Dawn newspaper.
Senior PPP leader Taj Haider confirmed that consensus had been reached within the party and Bilawal had been advised not to lead the poll campaign due to serious security threats.
"We have already lost Benazir Bhutto and will not risk losing Bilawal. The threats to his life are very real," Haider said on Friday.
Former premier Benazir Bhutto was killed in 2007 by a suicide bomber, just before the last general elections.
Haider did not say where Bilawal was at the moment.
However, the report quoted sources in PPP as saying that he had left Pakistan earlier this week and would not be returning before May 11.
In a video message released on April 23, the scion of the influential Bhutto family and son of President Asif Ali Zardari said he would join the PPP's election campaign but not lead it.
"I wanted to contest polls living amongst you; I wanted to launch the election campaign in the streets of my country alongside my workers, but we are at war against (a) mindset," Bilawal told PPP workers in the video that marked the launch of the party's campaign.
He claimed the murderers of his grandfather Zulfiqar Ali Bhutto and mother wanted to "eliminate" him as well.
PPP leaders had earlier said Bilawal would lead the campaign by addressing gatherings through video links.
However, he addressed only one small gathering of PPP workers in the party's traditional stronghold of Sindh.
Pakistan has witnessed a surge in violence targeted at campaigns and rallies in the run-up to the polls.
The banned Tehrik-e-Taliban Pakistan has announced it will target the PPP, Awami National Party and the Muttahida Qaumi Movement, which were partners in the last government, for their secular views and for launching operations against militants.
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