Everton midfielder Marouane Fellaini wants to seal a move to Manchester United this summer before his value increases next year.

With the World Cup looming large in 2014, Fellaini is reportedly worried that he could be priced out of a move to a bigger club next summer, especially if Belgium make an impression in Brazil, according to the Daily Mail.

United had a double bid for Baines and Fellaini worth £28 million ($43.6 million) turned down by Everton. Fellaini had a release clause of £23.5 million , which expired on July 31 and Everton currently value the midfielder at higher than that amount.

United are reportedly unwilling to even match the buyout clause figure but are preparing a bigger double bid for the Everton duo.

Everton manager Roberto Martinez criticized the manner in which United have gone about their transfer business for the two players.

"I have never seen Manchester United working in this manner before," Martinez said. "When you want a player you just do the business quietly, you get it done and that's it.

"I don't know if this is a new way of working at United. I don't expect a new bid. In fact, it wasn't even a bid because it never reached any sort of valuation of the players.

"There isn't an offer on the table where anyone would consider anything. If they'd matched the valuation maybe then you would listen to it but that hasn't been the situation."

Martinez believes United's offer for Fellaini was well short of his value. "If you invest a certain amount in a player and that player is one of the outstanding performers in the league, then I'm sure that price has gone up," he said. "It is common sense, isn't it?

"The market brings the valuation. There are aspects to consider like the age of the player and the length of his contract, but then it is very easy to look at the current price of that type of player in the market. That gives you a valuation.

"But I am not trying to fix a price for a player. It would be wrong to say that. I don't want to sell. But what is clear is if you want to buy a player and he's been a good performer, you must offer a higher value than what the club invested to get him. That's common sense."

The Everton manager, though, did not guarantee that either Fellaini or Baines would remain at Goodison Park after the transfer window closes on September 2.

"Nobody can guarantee a player will be here on 3 September, in the same way you can't guarantee you'll have a squad that is fully fit," he added.

"If I guaranteed now they will stay I would be lying because if Real Madrid decides to give us €100 million ($155 million) for a player I am sure we will not be able to stop that. I think we need to be realistic.

"I don't want to lose anyone and financially the club does not have to sell, which is very important."