The husband of a Christian woman who was sentenced to death four years ago under Pakistan’s blasphemy laws has pleaded for the country’s president to free his wife and allow her to move to France.

Lahore’s high court recently upheld the conviction against Aasia Bibi, who is among the best-known victim of laws that have been internationally condemned.

In a public letter, Ashiq Masih said his wife’s only hope was for an official pardon from the president, Mamnoon Hussain.

“No one should be killed for drinking a glass of water,” the letter said, referring to the incident in June 2009 when Bibi was accused of insulting the prophet Muhammad after a group of Muslim women in her home village of Itanwali, Punjab province, refused to drink from a glass used by a Christian.

Although it is not uncommon for such petty disputes to lead to deadly accusations of blasphemy, Bibi’s case attracted enormous attention after Salmaan Taseer, the then governor of Punjab, criticised the law and lobbied for a presidential pardon. His support caused widespread outrage and he was later assassinated by one of his bodyguards.

Since then, almost no politician has dared call for reform of the laws and it is extremely unlikely the present government will consider a pardon for Bibi, but it is also unlikely the mother of five will be executed as long as Pakistan follows an unofficial moratorium on the death sentence in order to maintain valuable trade concessions with the European Union.

Blasphemy prisoners risk being attacked or killed inside prison by fellow inmates or even guards.

In September, an elderly and mentally ill Pakistani-British citizen, Mohammad Asghar, was shot and injured by a police officer inside jail. His attacker had reportedly been incited to try to kill him by Mumtaz Qadri, the man responsible for the murder of Taseer, who is being held in the same jail.

In a sign of the strength of feelings among wide sections of the public, Qadri has been hailed as a hero and a mosque in Pakistan’s capital, Islamabad, has been named in his honour.

Masih said his wife was being kept in terrible conditions in the city of Multan and had survived only because her family was able to bring her fresh food and medicine.

“My prison cell has no windows and day and night are the same to me,” Bibi said in a message relayed by her husband. “But if I am still holding on today it is thanks to everyone who is trying to help me.”

Pakistan’s blasphemy laws originated during the British Raj, but were hardened in the 1980s when insults to Islam became a capital offence.

Critics say it is almost impossible to defend the accused, with judges fearful of throwing out cases and evidence often impossible to scrutinise for fear of repeating any alleged blasphemy.

The number of blasphemy cases, as well as vigilante attacks and killings of alleged blasphemers, has increased sharply in the past decade.

In his letter, Masih recalled how he and his family always “lived in peace” alongside their Muslim neighbours. “But for some years now the situation in Pakistan has changed because of just a few people, and we are afraid,” he said.

Ashiq Masih’s letter to Mamnoon Hussain

Yesterday, I returned from the prison in Multan where my wife, Aasia Bibi, was transferred eight months ago. Since Aasia was sentenced to death in November 2010 for drinking a glass of water from our village well, my family has lived in constant fear and under death threats. I live in hiding with my five children as near as possible to Aasia. She needs us very much to help keep her alive, to bring her medicine and good food when she is sick.

After my wife had spent four long years in prison in terrible conditions, we were hoping that the high court of Lahore would free my wife. She did not commit blasphemy, never. Since the court confirmed the death sentence on 16 October, we do not understand why our country, our beloved Pakistan, is so against us. Our family has always lived here in peace, and we never had any disturbance.

We are Christians but we respect Islam. Our neighbours are Muslims and we have always lived well with them in our little village. But for some years now the situation in Pakistan has changed because of just a few people, and we are afraid. Today many of our Muslim friends cannot understand why the Pakistani justice system is making our family suffer so much.

We are now trying our best to present the final case to the supreme court before 4 December. But we are convinced that Aasia will only be saved from being hanged if the venerable President Mammon Hussain grants her a pardon. No one should be killed for drinking a glass of water.

My five children and I have only survived thanks to the protection of a few faithful friends who risk their lives daily to help us. We are the husband and family of Aasia Bibi and many people want us to die. Thanks to our friend Anne-Isabelle Tollet, who has become our sister and helped us for four years now, we speak often about what is happening in Paris and the world to help save Aasia. Hearing that people are supporting Aasia from so far away is so important for us. It helps us to hold on. Every time I visit Aasia in prison I tell her the news. Sometimes it gives her the courage to keep going.

Just before taking the 10-hour journey to visit Aasia, I learned the wonderful news that Paris is offering to welcome Aasia and our family to Paris if she is freed. This is a huge honour and we are very humbled. I would like to offer my sincere thanks to you, Madam Mayor of Paris, and to say that we are immensely grateful for your concern. I hope that one day we will visit you alive, and not dead.

When I visited Aasia Bibi yesterday she asked me to give you this message: “My prison cell has no windows and day and night are the same to me, but if I am still holding on today it is thanks to everyone who is trying to help me. When my husband showed me the photographs of people I have never met drinking a glass of water for me, my heart overflowed. Ashiq told me that the city of Paris is offering to welcome our family. I send my deepest thanks to you Madam Mayor, and to all the kind people of Paris and across the world. You are my only hope of staying alive in this dungeon, so please don’t abandon me. I did not commit blasphemy.”

Ashiq Mashi, Pakistan, 17 November 2014