Last week, the government shifted a veteran anti-corruption investigator from cases against Bhutto, who lives in exile but still leads the Pakistan People's Party, the country's largest anti-Musharraf political group.
The move to transfer the corruption investigator fanned speculations that Musharraf, facing a bitter row with the opposition over his sacking of a senior judge, may sanction Bhutto's return to Pakistan.
"The Pakistan government's promise not to intervene is little more than hot air"
Jim H, USA
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Musharraf, who toppled Nawaz Sharif and seized power in a bloodless coup in 1999, has said in the past that both Sharif and Bhutto, who was elected prime minister in the 1980s and 1990s, have no further role to play in Pakistani politics.
Bhutto left Pakistan in 1999 to avoid arrest on various charges of graft in cases linked to her tenure as prime minister.
Bhutto has been dividing her time between London and the United Arab Emirates.
Sharif has also been living in exile in Saudi Arabia and London.