Atheist campaigner Richard Dawkins wants Pope Benedict XVI to be arrested during his state visit to Britain in September.

Dawkins and atheist author Christopher Hitchens have approached human rights lawyers over whether the Pope could be arrested over his alleged cover-up of child abuse by Catholic priests.

The Pope is due to visit London, Glasgow and Coventry during his state visit to the UK from September 16 to 19.

The atheist campaigners believe the Pope could be arrested using the same legal principle that led to the arrest of the late Chilean dictator Augusto Pinochet during his 1998 visit to Britain.

The Pope has faced intense scrutiny in recent weeks over his handling of child abuse cases in the US.

Over the weekend, it emerged that the then Cardinal Ratzinger had signed a letter in 1985 cautioning that the “good of the universal church” should be weighed up against any action taken against Californian priest Stephen Kiesle, who had a record of abusing boys.

Dawkins and Hitchens believe the Pope should be arrested for “crimes against humanity”.

“This is a man whose first instinct when his priests are caught with their pants down is to cover up the scandal and damn the young victims to silence," said Dawkins, author of The God Delusion.

“This man is not above or outside the law. The institutionalised concealment of child rape is a crime under any law and demands not private ceremonies of repentance or church-funded payoffs, but justice and punishment," said Hitchens, author of God is Not Great.

Their lawyers, Geoffrey Robertson and Mark Stephens, believe there is a case for the Pope’s arrest and that he cannot claim diplomatic immunity as he is does not head a state recognised by the UN.

“There is every possibility of legal action against the Pope occurring,” Stephens was quoted as saying by The Times. “Geoffrey and I have both come to the view that the Vatican is not actually a state in international law. It is not recognised by the UN, it does not have borders that are policed and its relations are not of a full diplomatic nature.”

The Vatican denied that the Pope had attempted to block the defrocking of Kiesle, suggesting that the abuse scandal had been orchestrated by opponents of the Pope.

Cardinal Angelo Sodano, dean of the College of Cardinals, told the Vatican newspaper L'Osservatore Romano: "The pope embodies moral truths that aren't accepted, and so, the shortcomings and errors of priests are used as weapons against the Church."

Security has been tightened for the Pope’s two-day visit to Malta this week over fears of protests in light of the abuse scandal. Posters promoting the Pope’s visit have been defaced by Adolf Hitler style moustaches and the word “paedophile”.

The Mediterranean island, which is 90 per cent Roman Catholic, has not escaped the abuse scandal rocking the Church. Many of the abuse claims on the island involve the St Joseph Orphanage at Santa Venera.

The Pope is visiting the island to mark 1950 years since the apostle Paul was shipwrecked there.