Tension between Bayern Munich and Barcelona has intensified over the future of Robert Lewandowski.

Bayern management have been left furious with Barca's negotiating tactics as they've sought to prise the Poland striker away from Munich.

With less than a year to run on his current deal, Barca have offered €40m for the 34 year-old, while Bayern are demanding €50m to sell - with the cash paid up front. The Germans' counter price also came with an insult.

Local reporter Raphael Honigstein has revealed: "Bayern Munich has told FC Barcelona that they do not want bonuses in any agreement for Robert Lewandowski and that they want all the money in advance in cash because Bayern believes that FC Barcelona will not exist in one or two years."

Bayern's insult was made just months after honorary president Uli Hoeness said: "Barcelona wants to hire Lewandowski when theyhad a debt of 1,300 million euros six months ago. In Germany they would have been bankrupt for a long time. The bankruptcy judge is at their door and they are making a millionaire offer to a Bayern player."