'The Interview' has been made available to iTunes users in North America.

The release of the controversial film, which centres on a meeting with North Korean leader Kim Jong Un, had been delayed amid terrorism threats, which prompted cinemas to refuse to screen the movie.

However, it has now been made available to rent or purchase on iTunes in North America.

In a statement, Apple said: ''We're pleased to offer The Interview for rental or purchase on the iTunes store.''

The film, which stars James Franco and Seth Rogen, was released on YouTube, Google Play and Xbox on Christmas Eve, while it was screened in selected US cinemas on Christmas Day.

It was recently confirmed that 'The Interview' has already become the number one online movie ever released by Sony.

As of December 27, the film had raked in more than $15 million and was downloaded more than two million times.

And with the movie having been made available to iTunes users in North America, the figures could rise substantially in the coming days.

Sony's initial decision to cancel the film's release had attracted significant criticism, including from President Barack Obama, who warned that it meant freedom of expression was under threat.