The former Archbishop of Canterbury Lord Carey is among 30 senior Christian leaders urging Christians of all denominations to vote according to their conscience in the approaching general election.

They make the call in a new Christian manifesto released on Easter Sunday. The ‘Westminster 2010: Declaration of Christian Conscience’ tells Christians to follow the guiding principles of their faith when they cast their vote in the general election, expected to be held on May 6.

The manifesto expresses support for marriage and freedom to live according to one’s religious beliefs, and opposition to assisted suicide and euthanasia. It also calls on Christians to defend the unborn, sick, disabled, poor and other vulnerable people.

Its release has been timed to send a message to all parliamentary candidates that Christians will support those who promote policies aimed at protecting vulnerable people and upholding the right of Christians to live according to Christian beliefs.

The leaders pledge to do what they can to ensure laws are just and fair “particularly in protecting vulnerable people”, and commit themselves to “seek to ensure that religious liberty and freedom of conscience are unequivocally protected against interference by the state and other threats, not only to individuals but also to institutions including families, charities, schools and religious communities”.

The manifesto is in part a response to recent high profile employment disputes involving Christians and the successful challenge by Christian leaders to aspects of the Equality Bill which would have restricted the rights of Christians to employ people who shared their Christian ethos.

The manifesto has been largely inspired by the Manhattan Declaration, drawn up by Christian leaders in the US last year to rally Christians of all denominations and traditions to defend the sanctity of life, traditional marriage, and religious liberty.

In a similar fashion to the Manhattan Declaration, Christians are being asked to sign up to Westminster 2010 via the website www.westminster2010.org.uk.

Signatories of the manifesto include former Bishop of Rochester Michael Nazir-Ali and Cardinal Keith O’Brien, leader of the Catholic Church in Scotland.

The document has been released amid an ongoing row over whether Christians in the UK are being persecuted because of their faith.

Lord Carey and Bishop Nazir-Ali are among the Christian leaders who claimed in recent weeks that the rights of Christians in the UK were not being upheld.

The Archbishop of Canterbury Dr Rowan Williams appeared to refute the claims in his Easter sermon on Sunday when he urged Christians in the UK not to equate opposition to their faith with the physical persecution suffered by believers in countries like Iraq and Nigeria.