A hard-hitting Scientology documentary slammed by John Travolta is unlikely to be aired in the UK because of fears that the broadcaster could be exposed to libel claims. Lawyers have warned that the differences in defamation law in Northern Ireland mean controversial US expose HBO's 'Going Clear' might not be broadcast by Sky Atlantic. The Alex Gibney-directed film, which alleges abusive practices at the religion's US headquarters, was due to premiere in the UK earlier this month to coincide with its American release. But the fact that Northern Ireland is not subject to the 2013 Defamation Act means Sky is set to postpone or cancel the show entirely, according to the Observer. Scroll down for video . A hard-hitting Scientology documentary slammed by John Travolta (pictured at a gala for the church in 2013) is unlikely to be aired in the UK because of fears that the broadcaster could be exposed to libel claims . This is because it could expose the broadcaster to libel claims from David Miscavige, the leader of the church, and other prominent scientologists. It mirrors the decision taken by British publishers Transworld to cancel their release of Lawrence Wright's Going Clear: Scientology, Hollywood and the Prison of Belief, on which the film is based. Hollywood star John Travolta slammed the film and said his decades of personal experience at the church have been positive. Speaking to the Tampa Bay Times he said: 'I've been so happy with my experience in the last 40 years...that I really don't have anything to say that would shed light on (a documentary) so decidedly negative.' The documentary claims to have revealed secrets about the church of Scientology, pictured is headquarters . Lawyers have warned that the show could expose the broadcaster to libel claims from David Miscavige, the leader of the church, and other prominent scientologists such as Tom Cruise, pictured at a conference . The programme would be shielded by libel laws in Britain which state that people or organisations must now show 'serious harm' to reputation. But the same documentary would be exposed to pre-reform libel laws in Northern Ireland because Sky is unable to differentiate its signal between regions for technical reasons. Sky has maintained the decision is a delay rather than a cancellation. A spokesman said: 'At present, Sky's transmission date for Going Clear has not been confirmed.' The church has condemned the film as a 'one-sided, bigoted propaganda built on falsehoods' and informed by former members –whom it calls 'misfits'. It is understood to have instructed solicitors in the UK to warn Sky it faces legal action if Going Clear is broadcast. The church said in a statement: 'The Church of Scientology will be entitled to seek the protection of both UK and Irish libel laws in the event that any false or defamatory content in this film is broadcast within these jurisdictions.' Going Clear examines the Church's founder, L. Ron Hubbard, the church's finances and its relationships with celebrities such as Tom Cruise and  Travolta. Libel lawyer Paul Tweed, who was involved in previous discussion with UK publisher Transworld, which dropped Going Clear, said a decision to broadcast would be based on commercial reasons. The church is understood to have instructed solicitors in the UK to warn Sky it faces legal action if Going Clear is broadcast, pictured is leader David Miscavige . Alex Gibney (left) directed the documentary and interviewed senior former members including Paul Haggis (right) 'Any client of mine, whether a journalist or a high-profile personality, is entitled to protect their reputation against false allegations,' he said. 'In terms of Sky's decision … they have to make absolutely certain that what they are broadcasting is not defamatory or untrue. If they have right on their side, they have nothing to fear.' Going Clear has been seen by more than 5.5 million people in the US and is likely to become second only to a film about Beyoncé as HBO’s most-watched documentary of the past decade. In a comment piece in the Los Angeles Times last week director Mr Gibney said: 'In the past, critics of the church have called for its tax exemption to be revoked because it is not a 'real religion'. I agree that tax-exemption isn't merited, but not for that reason. 'The Church of Scientology has a distinct belief system which, despite its somewhat strange cosmology – mocked by the TV show South Park and many others – is not essentially more strange than, say, the idea of a virgin birth. 'Scientologists are entitled to believe what they want to believe. And the IRS [Internal Revenue Service] website makes it clear anyone is entitled to start a religion without seeking IRS permission. To maintain the right to be tax-exempt, however, religions must fulfil certain requirements for charitable organisations. For example, they may not 'serve the private interests of any individual' and/or 'the organisation's purposes and activities may not be illegal or violate fundamental public policy'.'
Scientology exposé has been halted over differences in UK libel law . HBO's 'Going Clear' was due to be broadcast by Sky earlier this month . Lawyers warned church could sue because of Northern Ireland's libel law . John Travolta has slammed the documentary and said he would not watch .