Former US Senator Jim DeMint, has taken to YouTube to urge American citizens to fight against equal marriage, saying that the “health” of the US depends on it, and preserve marriage which “existed long before government”.

DeMint quit as Senator in December in order to take the top spot at the anti-gay campaign group, the Heritage Foundation.

In his most recent video he urges Americans to rally in Washington DC against equal marriage, as the Supreme Court gears up to take up two cases around equal marriage bans, and whether they are constitutional.

He says: “I want to speak with you today about something vitally important to the health of our nation; marriage. I want to encourage you in term to talk with your family and friends, and if you can, to make your voice heard right here in Washington DC.

“That day, and the next, the Supreme Court will hear challenges to laws that define marriage as a union of a man and a woman.

“Let’s stand and defend the institution of marriage, which existed long before government to provide children with mothers and fathers,” he continues.

He concludes: “Marriage strengthens civil society and limits government. You see, as our marriage culture weakens, big government grows. Just look at how our welfare state got bigger and bigger as the unwed, childbearing rate skyrocketed from single digits in the 1960s to over 40% of all births today.

“So it’s with good reason that 41 states affirm marriage as the union of a man and a woman. All Americans have the freedom to live as they choose, but no one has the right to redefine marriage for all of us.”

In 2010, DeMint was asked to apologise for saying gay people and unmarried pregnant women should be barred from teaching.

On 26 March, the court will take up the case of whether to overturn Proposition 8, which in 2008 added a clause to the Californian constitution stating that marriage could only be recognised by the state if it were between a man and a woman, causing widespread controversy.

The Supreme Court is also due on 27 March to hear evidence around the case of the Defense of Marriage Act (DOMA), which defines marriage as between a man and a woman, passed under President Bill Clinton in 1996.

Last week, the head of a well-known law firm and top attorney said that he expects the US Supreme Court to resoundingly support equal marriage, when it takes on two cases challenging equal marriage bans in America.

Earlier today, the former US Secretary of State Hillary Clinton, officially announced her support for equal marriage in a moving speech in which she calls moves towards equality “breathtaking and inspiring”.