The Episcopalians are set to become America's biggest Christian church to bless gay marriage.
The Witnessing and Blessing of a Lifelong Covenant rite, which was agreed by the Chamber of Bishops yesterday (9 July) and is expected to be passed by the House of Deputies this week, will come into effect in December.
With nearly 2 million followers, according to the National Council of Churches, the Episcopal Church will be the largest denomination to have a same-sex marriage liturgy.
It is the latest move by the institution in favor of LGBT equality.
The church approved its first gay bishop, Gene Robinson, nine years ago and now allows gay men and lesbians to join its ordained ministry.
The House of Bishops have also approved proposals which no longer discriminate against transgender people as candidates for the ministerial position.