Pakistani Christians in Britain have pleaded with David Cameron to do more for victims of Pakistan's stringent blasphemy laws.

Wilson Chowdhry, chairman of the British Pakistani Christian Association, raised his concerns during a meeting with the Prime Minister at 10 Downing Street.

The call is timely as this week an appeal hearing against the death sentence of Christian mother Asia Bibi for blasphemy was delayed by the Pakistani courts for the third time.

Mr Chowdhry said the Prime Minister had indicated he would raise the issue of the blasphemy laws with Pakistan's President Mamnoon Hussein during a forthcoming visit.

"Mr Cameron's promised efforts on behalf of the victims of Pakistan's blasphemy laws is welcome news," said Mr Chowdhry.

"However, against this we must not underestimate the deeply entrenched support for the blasphemy laws amongst the significant portion of the Pakistani population and elite that is, shall we say, rather retrogade.

"We look forward to hearing what response Mr Cameron receives."

Pakistan is one of the harshest places on earth for Christians, with churches and Christian neighbourhoods the victim of bombings and mob attacks.  Christian girls are often abducted and forced to convert to Islam and marry their abductors.  Many Pakistani Christians work in the lowest paid jobs because of their faith. 

In 2010, Bibi became the first woman in Pakistan's modern history to receive the death sentence for blasphemy.  Her family remains in hiding and there are fears for her life, even behind bars.  Two Pakistani politicians, Minorities Minister Shahbaz Bhatti and Punjab Governor Salman Taseer, were murdered after speaking up on her behalf and voicing concerns about the blasphemy laws.

Mr Chowdhry said international pressure was "a must to counter the intimidation of extremists calling for her death".

He appealed to people to sign the petition calling for her release here

Mr Cameron acknowledged in an address to church leaders last week that Christians were the most persecuted religion around the world. 

"We should stand up against persecution of Christians and other faith groups wherever and whenever we can," he said.