The mother of five has been on death row since November 2010 after being convicted of committing blasphemy during an argument with a Muslim woman over a bowl of water.
Despite denying the charge, she was arrested and imprisoned. She's been locked up ever since.
Her final appeal will be heard by Pakistan's Supreme Court on Thursday. If she fails it's expected she will be hanged within 30 days.
Minister of State of the Foreign and Commonwealth Office Baroness Anelay told Premier: "Her fate has been one that my colleagues in the House of Lords, across all parties, have raised concern.
"This is not something that divides us on party lines.
"The decision is tomorrow, I wouldn't want to say anything to disrupt that process, but we watch every second".
She said blasphemy laws were an issue that the UK Government "tries to discuss every day and try to persuade governments that they should look again at the legislation".
Asia Bibi's lawyer has told Premier she is suffering but staying strong in her faith.
Khalil Tahir Sindhu said: "Right now she is behind bars.
"She has not seen, unfortunately, the Sun or the Moon this year.
"She is very, very strong in her faith. There was so many attempts to convert her but she said 'no - I will remain faithful' and she has remained faithful."
Mr Justice Mian Saqib Nisar, Mr Justice Iqbal Hameedur Rahman and Mr Justice Manzoor Ahman Malik will rule on her appeal.
