A friend of Asia Bibi said the 54-year-old was being kept by officials alongside her husband in a locked room in the southern port city of Karachi.
Aman Ullah, who telephoned Ms Bibi on Friday, told Associated Press (AP): "She has no indication of when she will leave... they are not telling her why she cannot leave."
According to Mr Ullah, European diplomats assisting the mother-of-five were told her departure from the country shall not come in the short-term but "in the medium-term".
A member of Pakistan's government told AP "all possible measures" were being taken to ensure Asia Bibi's safety but she is a "free citizen" and able to travel at will.
In an email to the news agency, Information Minister Fawad Chaudhry said: "She is living with her family and given requisite security for safety".
Ms Bibi spent eight years on death row after being convicted of insulting Islam - an accusation she always denied.
Premier's Alex Williams speaking with Asia Bibi's husband, Ashiq, and daughter, Eisham, in 2018.
The allegation surfaced after she was involved in a disagreement with a group of Muslim women in 2009 over the use of a water cup.
She was acquitted in October last year - a decision upheld by the Supreme Court in Islamabad last month. Hard-line Islamists protested at her acquittal. They want her to be publicly executed.
There is speculation Ms Bibi wishes to leave Pakistan and join her daughters offered sanctuary in Canada.
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