Barkley, who came through the Everton youth ranks, has just over a year remaining on his current deal and was this week linked with a move to Chelsea. 

The Liverpool Echo reports that Everton are not planning to hold talks with the 23-year-old until the summer, but Koeman -- who faces a battle to retain striker Romelu Lukaku -- said he must commit if he is to continue his career at Goodison Park.

"I think every situation is different," he told reporters. "Ross is a boy from Everton, and what we need to show to him is the best reasons to stay. Of course his situation is different because Ross is running out, next season is his last year of his contract.

"Football is a business, you make decisions. He needs to sign a new contract or you sell the player."

Ross Barkley has contributed four goals and seven assists in 26 Premier League appearances so far this season.

Koeman said that was "no ultimatum" but added: "Football is a business. I think the player needs to understand this.

"It's not an ultimatum but I spoke to Ross about a new contract and it's up to the board to get that over the line. If not then the player could see a new future for himself, but that is normal, it's not strange talk."

Koeman highlighted the fact Southampton had sold Nathaniel Clyne to Liverpool durinh his time at St Mary's in a similar situation and added: "The player has to understand that if he doesn't sign a new contract, he needs to make a decision for the club so that they know what happens next year.

"Ultimatum is strong. I don't like that word."

Koeman, who took charge at Everton in the summer, had been critical of Barkley on several occasions earlier this season but he has recently praised the England international for his performances in an advanced role.