Archbishop of Canterbury: 'I could have done more'
The Archbishop of Canterbury has suggested he did too little to prevent the Anglican Church splitting over homosexuality.
Dr Williams, who retires in December after 10 years, told the Daily Telegraph he could have engaged sooner with US bishops over gay ordinations.
The "problem" with the job was that the "demands of the communion have grown and are growing", he said.
He suggested a "presidential figure" could be appointed to share duties.
The BBC's Robert Piggot said deep divisions had dogged Dr Williams' leadership of the Anglican communion.
The Telegraph interview was his most candid acceptance of personal blame for the rift over homosexuality, he added.
Dr Williams said that during his 10-year tenure he had "at various points, disappointed both conservatives and liberals".
"Most of them are quite willing to say so quite loudly," he added.
One of the biggest crises he had faced was the split between traditionalists and liberals over the ordination in the US of the first openly gay bishop, Gene Robinson.
"Thinking back over things I don't think I've got right over the last 10 years, I think it might have helped a lot if I'd gone sooner to the United States when things began to get difficult about the ordination of gay bishops, and engaged more directly with the American House of Bishops," he said.
He added: "I think the problem though, is that the demands of the communion, the administrative demands of the communion, have grown and are growing."
He said he thought it would be necessary in the future to "think about how that load is spread".
Of a possible new presidential role - someone "who can travel more readily" - he said the Archbishop of Canterbury should remain as the "head" of the Anglican communion and should keep "a primacy of honour".
But there should be "less a sense that the archbishop is expected to sort everything".
He admitted the Church had been "wrong" in the past over its approach to homosexuality.
"We've not exactly been on the forefront of pressing for civic equality for homosexual people and we were wrong about that," he said.
But he said legalising gay marriage would lead to a "tangle" between the Church and the government.
He said future monarchs may not have as strong a personal faith as the Queen but this need not weaken the links between the Church and the crown.
"As far as I can see, Prince Charles is a person of enormous personal interest in the spiritual life, in some of these big issues of symbolism which he's spoken about and written about very interestingly," he said.
"But [he is] probably a little more quizzical, let's say, about the institution of the Church of England."
And he called for more Christians to get involved in politics.
He said "people of faith" must do more "to encourage our own folk to be a bit more willing to go into politics and get their hands dirty".