Members of the British Parliament's lower house are expected to vote Tuesday in favor of a bill that would legalize same-sex marriage.

The House of Commons will hold a free vote in which members of the two top opposition parties, Labour and the Liberal Democrats, are expected to drive support for a bill. The legislation has split the Conservative Party, the dominant partner in Britain's ruling coalition.

If the bill passes, it may not be until another vote in May by the upper chamber before a clearer view of the legislation's fate emerges.

Prime Minister David Cameron, who leads the Conservatives, has spearheaded the drive for passing the legislation. He said in December he did not want gay people "excluded from a great institution."

Senior local Conservatives urged Cameron on Sunday to delay the vote, saying it could weaken the party and his chances for re-election.

Meanwhile, the new leader of the nation's established church, the Church of England, Justin Welby, has reiterated his opposition to legalization of same-sex marriage. However he placed the issue within the wider context of the activity facing the worldwide Anglican Communion, which he symbolically leads.

He was legally confirmed in his new position as Archbishop of Canterbury on Monday, but will be enthroned at Canterbury Cathedral on March 21.

"[I] support the Church of England's position on this. We have made many statements about this and I stick with that," he told The Independent newspaper.

"It's certainly a position that is being very widely debated at the moment," he said. "It's clear that this is a very difficult question for us here."

However he repeated an interviewer's statements that there are 80 million members of the Anglican Communion and 1.25 million regular worshippers in the United Kingdom.

"In the vast majority of the Anglican Communion this is not a particularly controversial issue. They're very much more worried about other things and those are the things I have to focus on as well. I have to look at the whole communion, not just this country."

Maria Miller a Conservative Party member of parliament who is also the Culture Secretary in the prime minister's cabinet, has been shepherding the bill through parliament.

She was quoted in the London newspaper, The Times, on Monday as saying gay marriage is the "right thing to do."

"The proposals for change are straightforward – if a couple love each other, then the State should not stop them getting married unless there is good reason – and being gay is not reason enough," she said.

"This bill is about choice. It is about giving those who want to get married the opportunity to do so, while protecting the rights of those who don't agree."

The Church of England has stated its opposition to the speed of the vote throughout the process, from the consultation period when the church submitted its views, to the recent publication of the proposed bill

On Friday it provided a briefing note to members of Parliament re-stating its case and bringing up uncertainties it sees ahead.

"This reshaping and unnecessary politicizing of a fundamental social institution, which predates church and state, did not feature in party manifestos, was not included in the last Queen's Speech and has no mandate from the government's own consultation exercise," the briefing note states.

The briefing stated there were unanswered questions about consummation and adultery, as well as uncertainty about teachers and the position of others holding traditional views of marriage working in the public service, as well as the risk of challenges to churches in the European courts despite protections provided in the legislation.

Those issues, the church states, "suggest that if the legislation becomes law it will be the focus for a series of continued legal disputes for years to come."