Manchester United will not allow David de Gea to force through a transfer to Real Madrid this summer and if necessary will hold the goalkeeper to his contract.

United have made it clear that De Gea will be able to leave for Real only if the Spanish club allow Sergio Ramos to move to Old Trafford. However, at the moment there is no prospect of this occurring, with the 29-year-old defender having been made the Real captain.

De Gea is with United on the pre-season tour of America and was set to feature in the opening match against Club América in Seattle to be played in the early hours of Saturday morning. The Spaniard is conducting himself professionally and is expected to continue to do so.

However, De Gea wants to move to Real and has turned down a lucrative new deal of at least £150,000 a week to extend his stay at United. If he becomes frustrated at his situation and the prospect of having to play out the final year of his current terms at Old Trafford, agitating for a move will not alter United’s stance.

As with Wayne Rooney two summers ago when the striker was unsettled and wanted to join Chelsea, United would have no hesitation in informing the 24-year-old he is the club’s player and will remain so until his contract expires.

Although United and Real are at an impasse regarding any De Gea-Ramos deal, there are still six weeks of the transfer window remaining and there is optimism at United that an agreement can be reached to resolve the situation.

Facebook Twitter Pinterest Sergio Ramos trains in Australia with Real Madrid, who have named him captain for the coming season. Photograph: Helios de la Rubia/Real Madrid via Getty Images

That is despite Real’s head coach, Rafael Benítez, saying on Friday that Ramos would not be leaving. “The president has already commented that he is staying with the club,” said Benítez, who added: “I see Sergio as an integral part of our team, he’s a winner and that’s what we need in our team.”

Louis van Gaal, though, is relaxed about the situation and would be prepared to wait until the final days of the window if required. Should De Gea finally leave for Real then United have a contingency plan to replace him. This could involve buying the Ajax goalkeeper Jasper Cillessen, who was Van Gaal’s No1 when the coach led Holland at the 2014 World Cup in Brazil. United believe that the Dutch club would allow Cillessen’s sale even if this was close to the 1 September deadline. If De Gea does stay, there is a recognition that it is very unlikely he will have a change of mind next season and sign the new contract and so is bound to leave for Real in summer 2016.

Should this happen, United are not concerned about him leaving for free and missing out on a fee of around £25m-plus. By then the club would have saved up to £10m owing to the player not having signed the fresh deal that offers him a far more lucrative salary than he was given in 2011 when he joined from Atlético Madrid.

United’s financial muscle means the club are willing to stand up to Real Madrid and end the usual practice of the 10-times European champions being able to cherry-pick whichever player they wish from any club. On 1 August the world record £750m kit deal with Adidas begins, an indicator of United’s robust position. In contrast the view at Old Trafford is that Real are in a less rosy position. The club face a flat level of income from their Spanish television contract over the next five years or so. They are tied into many of their larger commercial deals for some time so cannot expect too much of a financial injection in this area. And resources may be stretched by investing in many long-term contracts with players over the past two years. There is, though, a recognition of the deal to sell the naming rights of the Santiago Bernabéu to Abu Dhabi for around £15m a year.

If Ramos does not arrive Van Gaal is confident a defence that ranked fourth last season will improve further in the upcoming campaign following his strengthening of the midfield that will operate in front it. This week Bastian Schweinsteiger, the 30-year-old World Cup and Champions League winner, joined from Bayern Munich, along with Morgan Schneiderlin, who is 25 and is expected to add dynamism to the team.