Britain defended its foreign policy on Tuesday after the leader of the Roman Catholic Church in Scotland accused the government of pursuing an "anti-Christian" agenda.

Cardinal Keith O'Brien slammed government plans to increase aid to Pakistan without demanding a pledge for religious freedom in the Asian nation, where a Catholic government minister was murdered earlier this month.

"I urge (British Foreign Secretary) William Hague to obtain guarantees from foreign governments before they are given aid," O'Brien said.

"To increase aid to the Pakistan government when religious freedom is not upheld and those who speak up for religious freedom are gunned down is tantamount to an anti-Christian foreign policy," the cardinal claimed.

He was speaking at the launch of a report into Christian persecution by Catholic group, Aid to the Church in Need.

"Pressure should now be put on the government of Pakistan, and the governments of the Arab world as well, to ensure that religious freedom is upheld," he added.

"The provision of aid must require a commitment to human rights."

The British government recently announced it would double Pakistan aid to more than 445 million pounds (720 million dollars, 514 million euros).

Responding to the criticism, junior foreign minister Alistair Burt highlighted Britain's efforts made by the government to improve religious freedoms.

"We share the cardinal's concern about the plight of Christians facing persecution," Burt said in a statement.

"The effective promotion of human rights, including freedom of religion, is at the heart of our foreign policy."

Hague had set up a new human rights advisory group which at its first meeting in December had identified religious freedom as one of its key issues, he added.

"It is vital that Pakistan guarantees the rights of all its citizens, regardless of their faith or ethnicity."

Politician Shahbaz Bhatti was shot dead in broad daylight in a residential area of Islamabad on March 2.

Bhatti, a member of Pakistan's tiny Christian community, had been a vocal opponent of the country's controversial blasphemy law despite receiving death threats following the murder of another politician opposed to the law.