Faith leaders have joined a rally in London's Trafalgar Square calling for an amnesty for illegal immigrants.

|PIC1|The rally, which followed a mass at Westminster Cathedral, proposed a one-off "regularisation" of asylum-seekers and visa over-stayers in the UK for more than four years.

Similar schemes have already taken place in the EU, and the Strangers into Citizens campaign is hoping to highlight the current exploitation of illegal immigrants and potential future tax revenue.

Currently the Home Office estimates that there are approximately 570,000 illegal immigrants in the UK. Pressure group Migration Watch, however, says the figure is closer to 900,000.

The organisers of the rally have said they support the right to impose immigration restrictions, but say that there are more than 300,000 people in the UK who should be given legal status to remain in the country.

Campaigners explain that illegal immigrants are being exploited by employers who pay them meagre wages, which in turn deprives the country of millions of pounds in tax revenues.

In addition, calls were made for illegal immigrants that have been in the UK for more than fours years to be given two-year work permits, without a right to public benefits, which could open a way for them to obtain citizenship in the future.

The Archbishop of Westminster, Cardinal Murphy-O'Connor, who celebrated the special mass, reported that he was in "no way" intending to encourage future illegal immigration. However, he agreed with the campaigners, saying that many illegal immigrants had already been in the UK for years and "their rights should be protected".

He told the BBC: "Many of them are married, settled down and so they live in a kind of shadow land. That's not right and it's not fair."

Referring to the rally, he said: "Our Government and the governments all over the world must treat migrant workers with justice and with dignity."