Haqqani, a popular figure in the Washington diplomatic circuit before losing his post, has spent the past five weeks in the hilltop home of Pakistan's prime minister in Islamabad while fighting against allegations of his involvement in the memo that had sought U.S. help in preventing a military coup in Pakistan.
Haqqani and his supporters say he is being targeted by a nationalist, right-wing media and expressed fear he could be kidnapped or killed by the country's powerful spy agency, The New York Times reported.
Haqqani told the Times he has left his compound only three times thus far for legal proceedings and once for a dental appointment.
"I can go out for a walk but it is essentially like a house arrest," he said.
Haqqani and the government of Pakistani President Asif Ali Zardari have maintained they had no involvement with the document. The powerful Pakistani military also has dismissed plotting a coup.
The memo scandal has raised tensions between the military and civilian leaders.
Commenting on a three-member panel investigating the case, Idrees Ashraf, one of Haqqani's lawyers, said: "The probe is a fishing expedition because no charges have been filed against my client."
"Had I not returned [to Pakistan from Washington] given the murky and volatile political environment, I would have been deemed or described as guilty," Haqqani said.