Rob Dawson Correspondent 2 Minute Read

Jose Mourinho has asked Manchester United to show he has a long-term future by spending big money on Milan Skriniar of Inter Milan and Alessio Romagnoli of AC Milan in January, sources have told ESPN FC.

United boss Mourinho has come under pressure after a disappointing start to the season that sees his team seven points behind Premier League pacesetters Manchester City, Liverpool and Chelsea.

Privately, United have brushed off talk of appointing former Real Madrid coach Zinedine Zidane as Mourinho's replacement, but sources have told ESPN FC that Mourinho wants public support with money to spend during the window -- funds he believes he should have been given in the summer.

- Ogden: Mourinho demands public support

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Mourinho was expecting to spend in the region of £100 million ahead of the campaign as he looked to build on United's second-placed finish last season and bridge the gap to champions Manchester City.

He spent £68m -- signing Fred, Diogo Dalot and Lee Grant -- but missed out on bringing in a central defender.

Milan Skriniar, left, has emerged as a target for Manchester United. Photo by Claudio Villa - Inter/Inter via Getty Images

Sources have told ESPN FC that the manager believes the lack of reinforcements is the key reason for United's poor start and has urged executive vice-chairman Ed Woodward to rectify that situation in January.

According to sources, he is targeting Skriniar and Romagnoli to bolster his defence.

Mourinho had problems trying to convince United's decision-makers to make money available for Toby Alderweireld, 29, Jerome Boateng, 30, and Diogo Godin, 32, in the summer because of their age.

But both Skriniar and Romagnoli are 23 and sources have told ESPN FC that he is hopeful the board will be more open to purchasing a younger player.

Both would be available to play in the Champions League knockout rounds this season after changes to UEFA rules, with both valued at in the region of £40m.

United have spent £61m on two centre-halves -- Eric Bailly and Victor Lindelof -- since Mourinho's arrival in 2016, but doubts remain over both.

Bailly was substituted after just 18 minutes against Newcastle on Saturday, with United 2-0 down before they recovered to win 3-2, and Mourinho opted to move midfielder Scott McTominay to centre-back rather than bringing on Lindelof, who remained on the bench.

Chris Smalling, a defender Mourinho inherited, has made more appearances than both Bailly and Lindelof this season. He made 28 Premier League starts last season, compared with 13 for Lindelof and 11 for Bailly.