A youth choir booked to perform at major shopping centre in Edinburgh are part of a Texas “megachurch” that has been accused of being anti-gay and anti-abortionist.

The visit of The King's Project has been condemned by the Scottish Secular Society (SSS), which warned southern baptist ministries in the US were increasingly looking to use their money and religious influence to attempt to change laws in the UK and other countries.

Megan Crawford, chair of the SSS, who is herself a Texan, raised in a baptist church, said: “We are very concerned about megachurches who have a growing interest in coming over to Ireland, Scotland and England and pushing their extremely fundamentalist agenda. Why are they even allowed here to try to affect our laws and lives?”

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The King’s Project is the name given by the Prestonwood Baptist Church, of Plano Texas to a week-long trip by its Prestonwood Youth Choir to the North of England. Their mission is designed to drum up support for evangelical churches in the vicinity of Stockton-on-Tees, with one leader telling parents back home: “The Tees valley is lost and in desperate need of Jesus”.

But on Saturday, the 100-strong youth group were brought to Edinburgh’s Waverley Mall, in Princes Street, where they sang, performed and handed out prayer cards.

However there was no outward sign of what the church really stands for. In Texas, Jack Graham the head of the church has backed Donald Trump’s presidential election campaign and refuses to accept gay marriage laws. “The Scriptures’ teaching on marriage is non-negotiable... we cannot and will not affirm the moral acceptability of homosexual behaviour,” he said.

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The church has also campaigned against laws to promote the rights of transgender people and runs a school, Prestonwood Christian Academy which tells parents discussing sexuality with their children “Don’t be shocked if your children are very sympathetic, tolerant and even supportive of homosexuality – they have grown up with homosexuality as normative – you didn’t.” An advice sheet explains: “You didn’t grow up with homosexuals on every TV program you watched … with dozens of popular songs telling you that every someone is born that way and that every lifestyle choice is normal and needs to be embraced.”

Meanwhile the church, which has 36,000 members, also funds a pregnancy centre which claims to advise women in crisis but really boasts of persuading half of the 3,000 who visit a year to “choose life” for their baby “in a culture all too quick to snuff it out.”

A spokesman for Waverley Mall said: “This group requested permission to do an event on our roof. They had a similar event last year and we only had one complaint - from the Balmoral Hotel, about noise.

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“This year we requested they turn the music down a bit, but I’m not aware of them singing anything that would upset anybody.

“I was unaware of their views and my views are completely different. But the plaza was packed and it was well-received. We haven’t had any complaints this year.”

However Ms Crawford said: “Most people don’t appreciate these megachurches with their seemingly unlimited amounts of tax-free money coming over here and being allowed to attempt to affect our lives. They are extremely fundamentalist, with a view that marriage should be one male and one female, with sex only for procreation and anti abortion rights, and with a lot of young creationists in there.”

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