A Christian ministry has asked Britain's High Court to force London Mayor Boris Johnson to put anti-LGBT messages on the city's buses.

According to The Telegraph, Johnson banned Core Issues Trust's advertising that suggested gay men and lesbians could become "ex-gay" through reorientation therapy because they were offensive to the LGBT community and could spark backlash against the Christian community.

"The advertisement breached TfL’s advertising policy as in our view it contained a publicly controversial message and was likely to cause widespread offence to members of the public," a Transport for London (TfL) spokesperson told the paper.

Last year, the LGBT advocacy group Stonewall ran advertising on at least 1,000 London buses that said, "Some People Are Gay. Get Over It!"

In response, Core Issues Trust had planned to run advertisements reading, “Not Gay! Ex-Gay, Post-Gay and Proud. Get over it!”

"The advertisements indirectly advocated the possibility that some individuals benefit from sexual re-orientation therapy and as men and women who voluntarily seek change in sexual preference and expression, should be respected in their choices to seek help in this way," the Christian group said in a statement on Sunday.

Trust Director Dr. Mike Davidson, who describes himself as "ex-homosexual," claimed that Transport for London breached a contract a because Johnson intervened just hours before the ads were set to run.

"We were trying to reflect the fact that their a many different realities in terms of sexual identity with respect to same sex attraction," Davidson explained in a video that the group posted to YouTube. "Some people have same sex attractions but they don't identify with this idea of gay, a socio-political construct. Other people are ex-gay, they have had homosexual experiencem, but they have moved away from it. And still others would refer to themselves as post-gay because they've been through it but they've moved beyond it."

In the group's statement, Davidson insisted that the advertisements were an issue of free speech.

"In a truly democratic society people should be free to choose to change their behavior and move away from homosexual behavior if they wish," he opined. "The possibility that a section of the public will take ‘offense’ to a particular viewpoint is not a legitimate ground for restricting freedom of expression. The concept is simply being used by the State to censor opposing views and obliterate debate in the public sphere."

After Core Issues Trust attacked the pro-LGBT bus advertisements last year, Stonewall Chief Executive Ben Summerskill called the Christian group's "ex-gay" claims a "voodoo gay cure therapy."

"Life would be much easier if these organisations just admitted that they don’t like gay people," Summerskill said.

Watch this video from Core Issues Trust, broadcast Feb. 24, 2013.