Cristiano Ronaldo has said that a shock move to either Barcelona or one of Manchester United’s Premier League rivals is not out of the question.

The Real Madrid superstar has fuelled speculation of a potential move with his latest comments, but he also conceded that it would be “very complicated” to join a Premier League club other than United or Spanish rivals Barcelona.

"It’s a little more difficult,” Ronaldo told the Associated Press when considering whether he could one day join Barcelona or one of United’s rivals.

"There are things that you kind of already have an idea, that to play one day for Barcelona would be almost impossible, or to play for another English club other than Manchester - it’s very complicated.

"But that’s not 100 per cent guaranteed. As I said before, there are no certainties in football.”