The meeting was announced as the funerals of those killed in a suicide bombing in the North West Frontier Province (NWFP) were held on Sunday.
A suspected suicide bomber killed at least 25 people and wounded another 35 at an election rally of an opposition party on Saturday.
Hamid Nawaz, the interior minister, linked the blast to a wave of other bombings blamed on al-Qaeda and Taliban fighters that have killed more than 70 people this year.
ANP rally attacked
Zahid Khan, an ANP spokesman, said the party thought that the attack was intended to delay or disrupt elections.
The ANP has announced a three-day period of mourning.
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The government has blamed an al-Qaeda-linked tribal leader, Baitullah Mehsud, who is based in the South Waziristan region on the Afghan border, for Bhutto's assassination and many of the other recent attacks across the country.
Mehsud, the most wanted man in Pakistan, has denied the charge.
Kamal Hyder, Al Jazeera's correspondent in Islamabad, said: "The big question is who carried out the attack and why, and why so close to what is being considered the country's most crucial election in its history."