Japan's SoftBank has secured the backing of a major Sprint shareholder after raising its bid for the American wireless carrier to from $20.1bn to $21.6bn (£13.9bn) to counter a rival proposal by Dish Network, the US satellite firm.
The American hedge fund Paulson & Co, which is the second largest shareholder in Sprint, said it would support Softbank's proposal.
Although Dish's proposal is worth $25.5bn, Sprint's board has said the offer is not "actionable".
Dish said it was considering its next step. "We continue to believe that Sprint has tremendous value," the company said in a statement. "We will analyse the revised SoftBank bid as we consider our strategic options."
Sprint has given Dish until 18 June to come back with a revised bid. The company, which comes with lucrative wireless spectrum rights, also postponed a shareholder meeting that had been called for 12 June to consider the previous Softbank bid. The gathering will now take place on 25 June.