The first legislative chamber in California voted to allow same-sex marriage today, in a public snub to conservative Republican Governor Arnold Schwarzenegger.

Gov Schwarzenegger has previously said that if the bill was passed by both legislative chambers, he would use his powers as Governor to veto it, as he believes that the measure should be passed either by the courts or by a referendum.

The majority of lawmakers said that the state parliament should not wait for the Supreme Court to act on the issue, and passed the vote 42-43.

The author of the bill, Democrat Mark Leno told AP: “This does in fact provide equal marriage rights for all citizens of California.

“By denying a group of individuals the right to marry, we denigrate that entire group and deny them citizenship.”

The debate on the floor of the House was the lengthiest debate this year, but no insults were thrown, a feature which had marred previous debates on the subject.

The bill will now go to the state Senate, which is currently controlled by the Democrats.

Assemblyman Doug La Malfa, opponent of the bill, told AP: “There ought to be a few standards that stand the test of time, marriage being one of them.

“An institution that has lasted thousands of years in one form, that we would change it in the Legislature is pretty arrogant of us.”

California first began to recognise same-sex domestic partnerships in 2003, but gay couples in the state do not share full equality with married heterosexual couples.

Domestic partners do not receive income tax breaks, and are not eligible for Social Security beneficiary rules or veterans benefits.

Neither do they have legal rights to make medical decisions for their partners.

Massachusetts is the only state in the US that allows same-sex couples to marry.