Kenneth Branagh will not direct 'Thor 2'.

The actor-and-director - who was at the helm of 'Thor', which achieved worldwide ticket sales of $437 million - is not set to return for the sequel, which is set to see Chris Hemsworth reprising his role as the titular character, with the decision for him to step down reportedly "mutual and amicable".

Marvel Studios has made a full commitment to 'Thor 2', which Disney plans to release on July 26, 2013 in the US, reports.

Kenneth has previously hinted he might be interested in directing a sequel to 'Thor', describing the possibility as a "lovely challenge", but admitting the opinion of fans of the first movie would have a "crucial impact".

He said: "You know as well as I do, there's a passionate fan base out there that will say what they think.

"People will vote with their feet. And because it's such a big chunk of change for everybody involved, I think that's going to have a crucial, crucial impact.

"It would be a lovely challenge and problem to have should we do a second one. When I first got involved with this, I was so thrilled. The first big, really exciting moment when I started really going through the comic books was all the descriptions of powers."

It will not be the only time Australian actor Chris will be reprising the role - he will also be seen in ensemble movie 'The Avengers', which unites characters including Iron Man and Captain America.