Manchester United have not yet made an improved bid for Crystal Palace right-back Aaron Wan-Bissaka but are expected to, according to Sky Sports.
United have had an initial bid of £35m plus £15m in add-ons rejected by Palace.
Palace are understood not to be happy with the structure of the proposed deal, but it is believed they would accept an offer of between £45m and £50m up front for the England U21 international.
Some reports have claimed a fee has been agreed between United and Palace but Sky Sports News understands United have not been in contact since Monday.
Wan-Bissaka, who has three years remaining on his contract with Palace, is understood to be in favour of moving to United.
Palace are under no pressure to sell the 21-year-old, who featured 39 times in all competitions last season as the Eagles finished in 12th place.
United manager Ole Gunnar Solskjaer is keen to sign a right-back this summer following the departure of club captain Antonio Valencia.