Proposals for Old Trafford to be expanded to a capacity of 88,000 are likely to be scuppered by Manchester United's desire to back Jose Mourinho in the summer transfer market.

United had plans to increase the stadium from its current 75,000 seats to improve the atmosphere in the stands and the club's corporate hospitality.

While the proposals are under review, a club insider has told Sportsmail that the financial priority is to ensure the manager has the funds he needs to improve his squad.

Jose Mourinho could be granted the chance to go on another summer spending spree

Manchester United posted this picture of snow outside Old Trafford on Wednesday

Mourinho has sought talks with executive vice-chairman Ed Woodward about the subdued atmosphere at the ground, while supporters have criticised Old Trafford's layout, complaining that it does not make for a raucous environment.

However, despite having spent £300million since arriving in May 2016, the Portuguese's squad needs an upgrade.

Mourinho's men sit 13 points behind Premier League leaders Manchester City and, while United are still in the Champions League and FA Cup, they are relying on veterans such as Ashley Young and Antonio Valencia, both 32, to bridge the gap.

Manchester United had planned to increased Old Trafford's capacity to 88,000 from 75,000

An engineering breakthrough has increased the options for expansion. Previously it was thought that attempts to extend the Sir Bobby Charlton Stand, the smallest and oldest at the ground, would be impractical because of the railway line running behind it. Proposals which included building a tunnel over the line were seen as too expensive to be viable.

However, new plans allow for the stand to be raised higher without affecting the railway. Officials continue to explore ways to make it financially credible.

Pressure has increased recently after complaints over the ground's atmosphere and the corporate hospitality on offer.

United manager Mourinho and supporters have criticised the stadium's lack of atmosphere

Mourinho branded Old Trafford a 'quiet stadium' after the 2-0 win over Huddersfield Town last month and he is keen to solve the problem. United have consulted acoustics experts and in 2014-15 introduced a singing section in an attempt to increase noise levels.

The Manchester United Supporters Trust (MUST) called on the club recently to change the seating plan. They believe the large corporate section in the Stretford End diminishes the atmosphere.

Should a tier be added to the Sir Bobby Charlton Stand, it would provide around 7,500 seats and clear the way for two further quadrants in the corners, raising Old Trafford's capacity to around 88,000.

That would leave the ground's capacity behind only that of Wembley and Barcelona's Nou Camp in Europe. The increased capacity would also more than cover the cost of seats lost due to the proposed expansion of the disabled section.

It was thought that attempts to extend the Sir Bobby Charlton Stand would be impractical

Regarding hospitality, United have fallen behind rivals who have been able to expand their stadiums or move to new homes. An industry insider told Sportsmail that Manchester City now have the prime venue, saying: 'It's accepted that when it comes to corporate hospitality, City are streets ahead.

'United still have the big pull, because of the prestige and history of the club, (but) City's Tunnel Club is 10 years ahead of anything they have at Old Trafford.

'It's not that United's offering is not good, because it is. However, there is no wow factor. You're talking good at United, but out-of-this-world at City.'

United also struggle for space, and offer a Lancashire Package to supporters. Those who take that option use the corporate facilities at Emirates Old Trafford, the nearby home of Lancashire County Cricket Club, where they dine pre-match before traipsing to the football ground.