Barnsley and Peterborough have agreed fees with Colchester for midfielder George Moncur, according to Sky sources.
The clubs have matched Colchester's £500,000 asking price and also agreed to include a number of add-on clauses which could see the fee eventually rise to £750,000.
Moncur is yet to decide on a move, despite holding initial discussions with both sides.
Barnsley have been pursuing the 22-year-old since gaining promotion to the Championship in May and had a bid in the region of £400,000 rejected by Colchester last week.
'Moncur to leave Colchester'
George Moncur will be allowed to leave Colchester this summer – Sky sources
Peterborough have also been tracking Moncur and will hope to convince him to remain in League One next season.
Charlton, Peterborough's League One rivals, had a £150,000 offer for Moncur turned down in May.
Moncur joined Colchester on loan from West Ham in August 2014 before making the move permanent three months later.
He scored 14 times in 51 matches during the 2015-16 season, taking his tally for the club to 23 in 97 appearances.
Moncur was one of few bright spots in a disappointing campaign for Colchester, who will play their football in the bottom tier next season after finishing in 23rd spot in League One.