United made a £70m bid earlier in July but it is understood the Foxes want about £90m, a sum the Old Trafford club believe is unrealistic.

Maguire, 26, missed training on Monday because of illness, leading to rumours a deal was close.

However, the centre-back, who played in Leicester's friendly at Stoke City on Saturday, trained as normal on Tuesday.

The Foxes play their final pre-season game against Italian side Atalanta this Friday.

Maguire, who has also attracted interest from Premier League champions Manchester City, signed a five-year contract with Leicester last September.

United have already signed 21-year-olds Daniel James and Aaron Wan-Bissaka from Swansea City and Crystal Palace respectively, so the addition of Maguire could take their summer spending to more than £140m.