LONDON (Reuters) - Church of England priests will not be allowed to bless gay and lesbian weddings, or marry someone of the same sex themselves, according to new guidelines issued by the church, which is struggling to heal divides over homosexuality.

Same-sex marriage becomes legal in England next month, posing a dilemma for the Church of England, which is the mother church of the world's 80 million Anglicans and maintains that marriage is between a man and a woman.

England and Wales legalised secular same-sex civil partnerships in 2005. A church working group suggested last year that clergy allow gay and lesbian couples to mark and celebrate marriages held under the new legislation, as well as civil partnerships, in a religious service.

But following meetings last week, the church's bishops released guidelines at the weekend that ruled out any kind of blessing for gay marriages. Instead, they said, clergy could offer an informal prayer at their discretion and at the request of the couple.

"Services of blessing should not be provided. Clergy should respond pastorally and sensitively in other ways," said the guidance from the House of Bishops.

The Anglican Communion, which links Anglicans across and beyond the English-speaking world, has been split for years over gay rights and Biblical authority, especially since its U.S. branch - the Episcopal Church - ordained a gay bishop in 2003.

African traditionalists are strongly opposed to growing acceptance of homosexuality in the Anglican Communion and to a Church of England proposal for "facilitated conversations" on homosexuality.

The House of Bishops - one of three parts of the church's General Synod - also said people in a same-sex marriage should not be ordained as bishops, priests and deacons, nor should those in the ministry enter gay marriage.

"The House is not willing for those who are in a same-sex marriage to be ordained to any of the three orders of ministry," the bishops said. "In addition, it considers that it would not be appropriate conduct for someone in holy orders to enter into a same-sex marriage."

The legislation already forbids the Church of England and its sister Church in Wales from conducting same-sex marriages, although other religious groups can opt in if they want.

The Church of England had announced that it would address the issue of sexuality, saying it was aware it needed to reflect rapid changes in society and to address falling attendance rates and especially a failure to attract young people to the church.

The British parliament passed laws last year to allow gay marriages from 2014 in England and Wales. Scotland followed suit this month, becoming the 17th country to allow same-sex marriages.

Copies of the guidelines were sent to bishops and archbishops in other Anglican churches around the world, accompanied by a letter from the Archbishop of Canterbury Justin Welby and Archbishop of York John Sentamu.

They acknowledged the divisions in the church on homosexuality but said same-sex marriage was a "new reality" with implications for the Church of England that had to be discussed and addressed.

(Reporting by Belinda Goldsmith; editing by David Stamp)