The husband of Pakistan's assassinated former prime minister and opposition leader Benazir Bhutto says he thinks recent terrorist attacks in Pakistan are part of an attempt to rig upcoming parliamentary elections.

In an interview with Voice of America's Persian Service, Asif Ali Zardari said instability in Pakistan is part of an effort either to postpone the February 18 election or determine its winner.

Zardari, who co-chairs the Pakistan People's Party, says the party hopes to form a unity government. He said it is premature to say whether there would be an alliance with the party of former Prime Minister Nawaz Sharif. But Zardari said he is in regular communication with Mr. Sharif.

Zardari is handling the day-to-day leadership of the PPP while its new chairman, his son Bilwal Bhutto Zardari, completes his studies at Britain's Oxford University.

The 19-year-old has called for a United Nations investigation into his mother's death. But his father said Friday that the PPP has not yet made a formal request to the world body.

Zardari also said that the PPP does not trust the current investigation of his wife's death because it is under the supervision of the Pakistan government.