A Pakistani Christian girl accused of blasphemy in a case that has sparked international outcry must spend at least four more days in jail after a court adjourned a bail hearing on Monday.

Judge Muhammad Azam Khan has repeatedly delayed bail proceedings for Rimsha Masih, who was arrested last month accused of burning papers containing verses from the Koran in breach of Pakistan's blasphemy laws.

Khan on Monday again put back the hearing until September 7 following a request from a lawyer representing Rimsha's original accuser, neighbour Hammad Malik.

Rao Abdur Raheem, the lawyer, said the case should not be heard to show solidarity with a strike being observed by the bar association in neighbouring Punjab province, the largest organisation of its type in the country.

Rimsha's lawyer said the case against his client had collapsed.

"The prosecution has completely failed. There is nothing left in this case now," Raja Ikram, a lawyer representing Rimsha, told reporters after the adjournment.

Rimsha is being held at the high-security Adiyala jail in Rawalpindi, Islamabad's twin city and by Friday will have spent 22 days in custody.

Campaigners stepped up calls for her release after police on Saturday arrested a cleric for allegedly tampering with the evidence against Rimsha.

His deputy and two assistants said Hafiz Mohammed Khalid Chishti tried to bolster the case by planting pages from the Koran among burnt papers brought to him.

"Rimsha must be released now. The evidence has been proved false so there is no reason to keep her behind bars any more," Shamaun Alfred Gill, a spokesman for the All Pakistan Minorities Alliance told AFP.

According to a medical report, Rimsha is around 14 years old with a mental age below her true age, but some reports say she suffers from Down's Syndrome.

Western governments have expressed concern over her arrest.

But a prominent Muslim cleric calling for Rimsha's release and protection on Monday told the United States and other countries to "mind their own business".

Tahir Ashrafi, chairman of the All Pakistan Ulema Council, urged the government to set up a team, including intelligence agents, to investigate and "get to the bottom of the conspiracy and expose the real culprits".

"Our heads bowed in shame for what Chishti did," he said, but added there are "many others active behind the scene and they should be brought to justice".

Blasphemy is a very sensitive subject in the Pakistan, where 97 percent of the 180 million population are Muslims, and allegations of insulting Islam or the prophet Mohammed often prompt a furious public reaction.

Rights groups have called on Pakistan to reform its blasphemy legislation, which they say is often abused to settle personal vendettas.

In 2011, leading politician Salman Taseer and a Christian cabinet minister, Shahbaz Bhatti, were assassinated after calling for the law to be reformed.

Taseer's convicted killer is being held in the same jail as Rimsha.