Pranksters from the Chick-Fil-A Foundation have exchanged a fake coupon for a meal on the condition that they renounced their homosexuality.

The stunt, posted on YouTube, finds two men handing over a coupon to a slightly confused server at Chick-Fil-A that promises anyone who gives up their homosexuality a free chicken sandwich.

The company has been under-fire for months after its chief executive, Dan Cathy said that the company was “guilty as charged”, when asked about its perceived opposition to equal marriage.

The company, which is the second largest chicken fast food firm in the US, has donated millions of dollars to anti-gay groups including the Family Research Council, Exodus International and Focus on the Family.

In 2011, Mr Cathy rebutted accusations of being anti-gay, saying he and the company had “no agenda against anyone”.

But last year, he affirmed that Chick-Fil-A is opposed to equal marriage.

He said: “We are very much supportive of the family – the biblical definition of the family unit. We are a family-owned business, a family-led business, and we are married to our first wives. We give God thanks for that.

“We operate as a family business … our restaurants are typically led by families; some are single. We want to do anything we possibly can to strengthen families. We are very much committed to that.”