Banana firm Chiquita has rejected a takeover bid by Brazil's Cutrale and Safra groups, saying it was sticking to its plan to merge with European fruit seller Fyffes.
Chiquita said the offer from Brazil was "inadequate" and that it would not hold talks with the groups "at this time".
Fruit juice firm Cutrale and investment bank Safra made a $611m (£363m) bid for US-based Chiquita on Monday.
In March Chiquita and Irish fruit group Fyffes agreed to merge.
Monday's offer from the Brazilian businesses sent Chiquita shares 31% higher, while Fyffes fell 15%.
A Chiquita-Fyffes merger would create the world's largest banana supplier, with $4.6bn in annual revenues.
The deal would allow Chiquita to avoid higher US taxes by relocating its statutory headquarters to Ireland.