The archbishop of Canterbury has apologised for the “hurt and pain” the Anglican church has inflicted on LGBT people as he attempted to defend the decision to sanction the liberal US church for allowing same-sex marriage. Justin Welby’s remarks came at the end of a week-long summit of the world’s Anglican leaders, in which he sought to soothe divisions caused by the decision on Thursday to uphold a “traditional doctrine” of marriage as “between a man and a woman in faithful, lifelong union”.

Dozens of gay rights activists, many of them refugees from African countries, descended on Canterbury Cathedral to chant “Shame on you” where the 38 primates of the Anglican communion had been meeting to resolve deep divisions over gay rights.

The US Episcopal church has been banned from representation on key bodies and barred from voting on issues relating to doctrine or strategy for three years. However, it will remain a member of the Anglican communion. Liberal Anglicans responded to the de facto sanctions and the reaffirmation of traditional biblical teaching on marriage with anger and dismay. At the other end of the spectrum, hardline conservative Anglicans said the statement was a step in the right direction but did not go far enough in forcing US liberals to repent.