Thousands of Christian lawyers plan to ask the Queen, as defender of the Church of England, to help stop the government from imposing new gay rights laws on Britain.

They will ask the Queen to make the case to Tony Blair that the proposed Sexual Orientation Regulations discriminate against Christians.

The laws, meant to come into force in April, are supposed to prevent discrimination against gays. But the Church of England has pointed out that priests could be sued for refusing to bless same-sex civil partnerships under the rules.

Catholics have warned they will close their adoption agencies rather than be forced to allow gay couples to adopt children.

In addition, black churches have added their voices to the protest, saying pastors and churchgoers would go to jail rather than accept rules that would mean they had to open their meeting halls to gay lobby groups.

The plea to the Queen is being made by the Christian Concern for Our Nation, an offshoot of the Lawyers' Christian Fellowship, a group which lists more than 2,000 barristers and solicitors among its members.

The petition warns the Queen that the rules are a serious affront to the gospel.

It reads: 'The regulations purport to eliminate discrimination on the grounds of sexual orientation, but have the consequence of discriminating heavily against Christians of all backgrounds and denominations who hold firm to the very faith which you pledged to uphold in your coronation oath.'

The Queen does not have the power to block the introduction of the rules, but could raise her concerns during her regular meetings with Tony Blair.

Any indication of concern from Buckingham Palace would increase pressure on ministers to scrap the proposals, which have come into force in Northern Ireland.

The regulations are expected to have an impact on religious believers in business. Christian hoteliers will be compelled to rent rooms to gay couples while Christian or Muslim printers will be unable to refuse to print homosexual magazines or advertisements.

The final version of the UK rules, which the government has produced supposedly to meet the demands of a European Directive, has yet to be published.

People found guilty of discrimination in Northern Ireland will be fined between £500 and £1,000 for a first offence. Subsequent serious offences can attract penalties of up to £25,000.

The regulations have proved so controversial that Ruth Kelly, the Communities and Local Government Secretary, last year suspended their introduction into Britain for six months after her department was unexpectedly deluged with thousands of hostile responses to the consultation exercise.