Norwich City are thought to have told West Ham United that they will have to increase their offer for striker Grant Holt.
Despite having a transfer request recently turned down, the 31-year-old still wants to leave the club this summer.
Having had an initial bid of £4m rejected, the Hammers will now have to pay £6m for his services, according to The Mirror.
Holt was Norwich's top scorer last season with 17 goals in all competitions.