Former Pakistani Prime Minister Benazir Bhutto has been banned from leaving the country, her Pakistan People's Party (PPP) says.
Ms Bhutto says she has not been given proper security
PPP spokesman Farhatullah Babar told the BBC the party had written to the interior ministry over the issue.
Ms Bhutto survived an assassination attempt on Thursday on her return to the country after years of self-imposed exile. Nearly 140 died in the attack.
The government often bans opponents from leaving Pakistan.
The BBC's M Ilyas Khan in Karachi says that the ban may be a move to put pressure on Ms Bhutto in her negotiations with the government.
The interior ministry has not commented on the ban.
Ms Bhutto's family did not accompany her on her return to Pakistan.
Farhatullah Babar told the BBC that the ban on Ms Bhutto leaving the country had been re-imposed after her return.
It had been in place for many years but was supposed to have been lifted as part of an amnesty against prosecution granted to her by President Musharraf earlier this month.
Meanwhile Ms Bhutto says she will start campaigning soon for parliamentary elections due in the coming months.
Thursday's blasts took place after night fell
But she will not hold mass public rallies to minimise the threat of more bloodshed.
"The party decided I should go from Karachi to Islamabad, Lahore or Larkana (Ms Bhutto's hometown) in the next couple of days," the Associated Press reports her as saying.
"We will be not be holding public rallies but will be travelling to meet the people in other provinces."
Ms Bhutto also said in an article in the Wall Street Journal that the PPP would look at other ways of campaigning, such as the use of taped messages broadcast in village centres.
Ms Bhutto's supporters have been highly critical of the government and members of the security forces since Thursday's bomb attacks in Karachi.
Two bombs exploded as Ms Bhutto was leading a cavalcade past hundreds of thousands of jubilant PPP supporters on her return to the country.
She has said that "very powerful figures" were behind the assassination attempt and that the government had not given her proper security.
On Tuesday Deputy Information Minister Tariq Azim Khan said that the PPP had told police that the Chief Minister of Punjab province, Chaudhry Pervez Elahi, was part of a conspiracy against Ms Bhutto.
Ms Bhutto, who has twice served as prime minister, left Pakistan to escape corruption charges.
Her advisers and President Musharraf have been in protracted negotiations on a power-sharing agreement.
Gen Musharraf has come under heavy pressure from the United States to reach a deal with her to increase the legitimacy and popularity of his government.
He seized power in a coup in 1999. His popularity has been declining, partly because of the military's inability to defeat pro-Taleban militants who control swathes of territory along the border with Afghanistan.