Ahmed, who came to the UK in the late 1960s, had dual British and Pakistani citizenship at the time of his sentencing.
His British citizenship was stripped by the court after he was jailed and he was expected to be deported when his sentence ended.
Earlier this week, victims of the gang were told that provisions of the Immigration Act 1971 prohibit the removal of any Commonwealth citizen who arrived in the UK before 1973 and has been in the country for five years.
The BBC understands the UK Government is considering whether the 1971 law could be changed by amending the Immigration and Asylum Bill currently going through Parliament.
But once all legislative obstacles are cleared, the UK government will have to face the diplomatic challenge of getting Pakistan to agree to accept Ahmed’s deportation to the country.
This will require cooperation from the Pakistani authorities, which has not been achieved in similar cases in the past.
Pakistan had previously refused to return two of Ahmed’s associates from the nine-member Rochdale grooming gang.
Qari Abdul Rauf and Adil Khan could not be deported despite having their British citizenship revoked in 2018.
Conservative shadow home secretary Chris Philp said the government should consider cutting foreign aid to Pakistan if it refuses to take Ahmed back.
He told GB News: “If a British citizen commits a criminal offense somewhere else or is in another country illegally, we of course take our citizens back.
“So we expect other countries like Pakistan to do the same when the boot is on the other foot.”
Ahmed was jailed for 22 years in 2012 and was one of nine men at the Rochdale grooming gang trial found guilty of crimes against children.
Police said that up to 50 girls could have been victims of the gang, and that many of them came from chaotic, “municipal” backgrounds.
Judge Gerald Clifton said the victims were treated “as if they were worthless and had no respect” because they were not part of the gang’s community or religion.
Greater Manchester Police said at the time that there was no “racial or cultural” element to the crimes.
The report later found that police took no action despite numerous concerns being raised. It said there were “multiple serious violations” by police and local authorities.