[Updated at 3:27 p.m. ET] A little clarification: The bill would, as drafted, enable religious organizations in the United Kingdom to conduct same-sex marriages if they wish.

[Updated at 3:14 p.m. ET] More details on the vote on a bill that would legalize same-sex marriage in the United Kingdom: The second reading of the bill passed in a 400-175 vote Tuesday.

The bill will be up for further debate in the House of Commons, and it still would need to go though other stages, including another vote in the House of Commons and approval in the House of Lords, before it can become law.

[Updated at 2:35 p.m. ET] The UK House of Commons has passed a bill to introduce same-sex marriage in the country.

The legislation still must go through several more stages, including approval in the House of Lords, before it can become law.

[Posted at 9:23 a.m. ET] UK lawmakers are to vote on a bill to introduce same-sex marriage Tuesday, an issue that has prompted widespread rebellion within Prime Minister David Cameron's Conservative Party.

Three top party members appealed to Conservative MPs to get behind the controversial legislation in a letter published in the Telegraph newspaper Tuesday.