"I would like to go back to Pakistan sooner rather than later but General [Pervez] Musharraf [Pakistan's president] still is opposed to my return," she said.
There is speculation that Bhutto will join forces with Musharraf, who she reportedly had a meeting with last month, in the next elections.
Bhutto said she had a "confidential understanding" over her return from self-imposed exile and on her demand that he should stand down from the army.
"He's prepared for my return to Pakistan but the timing of it is under dispute between the two of us," she said.
Concessions
Bhutto has made clear that any deal with Musharraf would be dependent on the president making several concessions by the end of August.
She has requested Musharraf lift a ban on politicians serving a third term as prime minister, which excludes her from the post.
Bhutto became the first female prime minister in the Muslim world when she was elected in 1988.
She was deposed in 1990, re-elected in 1993, and ousted again in 1996 amid charges of corruption and mismanagement.
Asked when she planned to return, she said she was thinking of between September and December.
"I'm expecting the general elections to be called some time in October or November, but if I had my little Aladdin's lamp then I would ask the genie to get me there by Eid which falls in October," she said.
The Eid holiday is expected to start around October 13 this year in Pakistan.