The winger is out of contract at the end of the season and talks have been at a standstill.
Now Barca’s sporting director Mateu Alemany has declared that Dembele has turned down fresh terms.
The Nou Camp side now wish to sell the France international before this month’s window is over.
Alemany said: “It’s clear that Dembélé does not want to continue with Barcelona. He doesn’t want to be part of our project.
“We told Dembélé he has to leave immediately. We expect Ousmane to be sold before January 31.”
Barcelona manager Xavi insisted earlier this week that Dembele, who joined the Spanish giants from Borussia Dortmund for a fee of up to £135.5 million in 2017, must sign a new deal or depart.
Xavi said: “Either the player renews or we look for an exit for the player - there is no other possibility.
“We are in a complicated situation and we have been very clear with Ousmane.”
Will Liverpool sign Ousmane Dembele?
Liverpool are one of several clubs linked with the winger.
Reds boss Jurgen Klopp is a huge admirer of the 24-year-old. He previously tried to bring him to Anfield in the summer of 2016 before he opted for Dortmund when leaving Rennes.
In fact, Dembele admitted that he met with Klopp in Paris but his heart was set on Dortmund.
Ousmane has struggled with various injuries during his time at Barcelona.
However, he’s a player who has prodigious talent and is still yet to hit his peak aged 24.
Kopites would certainly like to see Klopp add sufficient cover and competition for Mo Salah and Sadio Mane.
But much depends if the Reds have the funds available to make a swoop in January.
Liverpool traditionally are not active in the winter market and leave their main business until the summer.
Wages demands may also be a problem.
Premier League rivals Chelsea, Manchester United and newly-rich Newcastle United have all been linked.