The club, based at Old Trafford, has warned that if the bid is not accepted, they may cease negotiations with the Blues.
Chelsea are believed to value the English player at £70m.
Yet, United considers this valuation to be excessive, especially given that Mount’s contract only has a year remaining and extension discussions have come to a halt.
Previous offers from United, amounting to £40m and £50m for Mount, were turned down by Chelsea.
‘Outstanding talent’ – what can Mount add to Man Utd?
Erik ten Hag, the United manager, aims for Mount to be his initial signing this summer. He wants to bolster his team following their qualification for the Champions League in the upcoming season.
It is not expected that personal terms would present a hurdle, and United is confident that Mount is interested in transferring to Old Trafford.
Since his debut in 2019, Mount has scored 33 goals in 195 games for Chelsea. He missed the end of the domestic season due to an injury, causing Chelsea to end at 12th, their lowest finish in over 25 years.
Mount helped Chelsea secure the Champions League in 2021 and was a key player in their 1-0 victory over Manchester City in the finals. He also won the Fifa Club World Cup and Uefa Super Cup with the Blues.
The 24-year-old has represented England 36 times, scoring five goals, and was included in Gareth Southgate’s team for the 2022 World Cup in Qatar.
Mount started his career in Chelsea’s academy before a loan to Dutch team Vitesse for the 2017-18 season, during which he scored nine goals in 29 Eredivisie matches.
The subsequent season he was loaned to Derby County, where he scored eight goals in 35 Championship games under manager Frank Lampard, despite the team’s loss to Aston Villa in the play-off final.
In 2019, Mount returned to Chelsea and, under the then-newly appointed Lampard, quickly became an indispensable player.
Recently, Mauricio Pochettino, former Tottenham boss, was appointed Chelsea’s new manager, taking over from interim manager Lampard who replaced the sacked Graham Potter.
Unless the valuation is met, Chelsea refuses to sell – analysis
Alex Howell, Sport Newes Center
The situation surrounding Mason Mount has been escalating for a while and now seems to be reaching its conclusion.
Chelsea would like to retain Mount, but his contract status, the impasse in negotiations, and Manchester United’s relentless pursuit suggest the outcome is likely one-sided.
Todd Boehly and the Clearlake group, after acquiring the club, emphasized their intention not to allow players’ contracts to enter the last two years. They suffered a significant loss when Antonio Rudiger moved to Real Madrid for free, leaving them to scramble in the transfer market.
Last year, Chelsea extended two contract offers to Mount, with salaries comparable to those of other big-name players.
Chelsea even contemplated a year’s extension to Mount’s contract as a possible resolution, offering him increased pay and more time to reach an agreement. Yet, like the previous offers, it was declined.
The main stumbling block in these negotiations appears to be the wage agreement between Chelsea and Mount.
Latest Chelsea news, analysis and fan views
Get Blues news notifications
Listen to the latest The Far Post podcast
Our coverage of Chelsea is more comprehensive than ever – here’s everything you need to stay in the loop
Everything Chelsea – your one-stop for all top content