Lawmakers in the US state of Delaware have voted 12 to 9 in favour of a bill to legalise equal marriage on Tuesday, making the Diamond State the 11th to allow same-sex marriage.

The vote in the Senate followed a vote in the General Assembly with 23 votes to 18 two weeks ago. The bill has the support of Governor Jack Markell, who has this evening signed the bill into law.

The bill explicitly aims to respect religious freedom, in that no religious organisation would be forced to marry anyone against their beliefs.

The legislation which aims to strike down a ban on equal marriage, which was implemented in 1996, and to allow same-sex couples to marry.

The law comes into effect on the 1st July 2013.

Marc Solomon, national campaign director of Freedom to Marry said: “Today’s historic vote makes Delaware the eleventh state across the U.S. where loving and committed couples can share in the joy and protections that marriage brings. As happy couples and their loved ones celebrate and prepare for the first weddings in Delaware – following the win in Rhode Island just a few days ago – this milestone sends yet another message to the Supreme Court that it’s time for marriage for all Americans. Freedom to Marry is proud of its work with Equality Delaware to secure this victory, and we look forward to surging forward and continuing the momentum in Illinois and Minnesota later this month.”

On introducing this bill, Markell said he was hopeful that it would pass given the Democratic control over both the upper and lower chambers of the legislature, but did go on to say ”nothing is sure until it’s done.”

The US state of Rhode Island last Thursday became the tenth state to allow equal marriage, as its Governor signed the bill into law, after it passed a second vote in the House by a very wide margin.

The US Supreme Court recently heard arguments around Proposition 8, the state of California’s ban on equal marriage. During the hearing, the justices questioned the meaning of marriage, and challenged arguments for the ban.

One day prior, the Supreme Court Justices indicated a possible interest in striking down the Defense of Marriage Act (DOMA), as it heard arguments around the issue.

A decision by the Supreme Court is expected in both cases by the end of June.