Manchester United have stepped up their pursuit of highly-rated Porto winger James Rodriguez.

Reports in the Portuguese media suggest, the Portuguese champions have rejected a massive £30 million ($47 million) bid for the 20-year-old.

Rodriguez reportedly has a £40 million ($62 million) buy-out clause in his contract, which has four years left to run, according to the Daily Mail.

Rodriguez is a tricky winger who can play on either flanks and even as a forward down the middle. The player, who will turn 21 in a couple of week's time, has been often compared to Cristiano Ronaldo for their similarities in the style of play and is being hailed in his native Colombia as the successor to the great Carlos Valderrama.

It is understood, Sir Alex Ferguson, who has sent out numerous scouts to watch the Colombian player play over the past couple of years, has made the winger one of his major targets for the summer.

With the increasing speculation about Nani's departure, United have stepped up their interest in Rodriguez. Ferguson is reportedly determined to land the forward, regardless of whether Nani leaves this summer or not.

United have offered the likes of Anderson as part of any deal, but Porto have rejected such a proposal.

Porto are reluctant to let go of one of their brightest prospects, and will hold out for the full £40 million.

It is highly unlikely United's American owners will sanction such an expensive deal with the club heavily in debt. However, Rodriguez's signing could appease the fans, who are worried about their club's lack of financial power in the transfer market, after they lost out to Eden Hazard, who signed for European champions Chelsea.