ISLAMABAD - The husband of a Pakistani Christian woman sentenced to death for blasphemy four years ago has written to the President to ask for her to be pardoned and allowed to be taken to France.

Asia Bibi has been on death row since November 2010 after she was found guilty of making derogatory remarks about the Holy Prophet Muhammad (PBUH) during an argument with a Muslim woman.

A high court in Lahore confirmed the death sentence last month, dashing hopes it might be commuted to a jail term.

"We are convinced that Asia will only be saved from being hanged if the venerable President (Mamnoon) Hussain grants her a pardon. No one should be killed for drinking a glass of water," husband Ashiq Masih wrote in an open letter dated November 17 and published by the New York Times. Paris Mayor Anne Hidalgo has said the couple are welcomed in the City, and Masih quoted his wife as stating she sent her "deepest thanks to you Madame Mayor, and to all the kind people of Paris and across the world".

Masih added his wife was not guilty of blasphemy.

The plea for being allowed to move to Paris comes days after the Mayor of the City Anne Hidalgo requested President Mamnoon Hussain to grant her a pardon.

Senior Opposition leader Bruno Retailleau on Wednesday asked French President Francois Hollande to intervene in the case.

Masih, 50, lives in hiding with two of his five children and has to keep his identity secret as he scrapes together a living as a daily labourer.

He visits his wife once a month, making a five and a half hour journey to her jail in Multan in southern Punjab.

The allegations against Asia Bibi date back to June 2009, when she was labouring in a field and a row broke out with some Muslim women she was working with.

She was asked to fetch water, but the Muslim woman objected,stating that as a non-Muslim she was unfit to touch the water bowl.

A few days later the woman went to a local cleric and put forward the blasphemy allegations.

Amnesty International has raised "serious concerns" about the fairness of her trial and has called for her release.

Pakistan has never executed anyone for blasphemy and has had a de-facto moratorium on civilian executions since 2008.