'Iron Man 3' has become the fifth highest grossing film of all time.

The Marvel comic book adaptation starring Robert Downey Jr. has proven incredibly popular with superhero fans, grossing a whopping $1.14bn (£760.5m) worldwide in just one month and knocking 2011's 'Transformers: Dark of the Moon' out of the top five movies of all time, according to official box office figures.

The film - which opened in the UK in April and in May in the US - ranks just behind 'Harry Potter and the Deathly Hallows Part 2's $1.34bn (£889m) takings in 2011.

'The Avengers' ranks at number three, with a worldwide tally of $1.51bn (£1bn). The team-up film cemented the public's interest in superhero mythology, and also features Robert Downey Jr.'s titular Iron Man character.

James Cameron's epic big budget adventures, 'Avatar' and 'Titanic', will be hard to beat, however, and remain ruling box office champions.

'Avatar' surpassed 'Titanic' as the highest-grossing film ever in 2010, with both having both made more than $2bn (£1.32bn) worldwide.

'Iron Man 3' actress Gwyneth Paltrow has credited talented leading man Downey, who plays billionaire superhero Tony Stark, with the smash success of the franchise.

She recently said: ''Personally, I think it would be very hard for someone to step into Iron Man, because it is so Robert.

''You've got pathos, you've got humour, you've got a facility with language and improvisation and an incredible pain underneath it all. It's difficult to replicate that.''