A mass rally has called for a one-off "earned amnesty" for hundreds of thousands of illegal immigrants living in the UK.
The Strangers Into Citizens campaign was joined by faith leaders, immigrants from across the world, community activists and church groups in a gathering in Trafalgar Square, central London.
The campaign is calling for a two-year work permit, without access to benefits, for "irregular" migrants - refused asylum seekers or visa overstayers - who have been in the country for four years or more.
Addressing the rally, the leader of Catholics in England and Wales, Cardinal Cormac Murphy-O'Connor, said immigrants living and working in the country deserved to be treated with "fairness, with justice and with dignity".
He said: "Our Government and the governments all over the world must treat migrant workers with justice and with dignity.
"That is why I am so glad to be associated with fellow Christians and people of other faiths and with politicians who are determined to see that before long these people who we say are strangers in fact become citizens."
The rally, attended by thousands, came after a Mass at Westminster Cathedral for migrant workers.
A colourful procession through Whitehall before the rally featured drummers, whistle-blowers, and Latin American bands, playing in spite of driving rain at times.
Some carried banners reading: "Abolish all racist immigration controls." Other banners read: "No one is illegal. Regularisation for all."
Under the proposals put by the campaign, those qualifying for a work permit would be given indefinite leave to remain at the end of the two-year period subject to criteria such as an English test, no criminal record and employer and sponsor references.
