The Catalan chief has again criticised Neymar over his conduct in moving to Paris after his world-record €222 million release clause was paid by the Ligue 1 giants.
Bartomeu was unable to prevent the Brazilian superstar's departure in August and, after being labelled a "joke" by the player, has now accused him and his representatives of a lack of honesty.
"We believed them [Neymar and his advisors] too much," Bartomeu told La2.
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When a player wants to leave he must be honest, as Alexis [Sanchez], Pedro or Cesc [Fabregas] did.
The 54-year-old reiterated his stance of not wanting to keep players who are unhappy at the Camp Nou, but expected Neymar to sign a new deal rather than leave for the Parc des Princes.
"We will not hurt a player that is not happy," he said.
Bartomeu also commented on the future of club captain Andres Iniesta who, he says, has the power to decide how long he wants to wear the Barcelona shirt.
"He will decide how long he wants to stay," he said.
"We want to him to stay with the club and have a special contract, because he deserves to decide when he wants to leave.
"He is an inspiration for all and symbolises what we all want for the club. He is playing well and helping the team, and I think he is closer to telling us 'yes'."
The fallout from Neymar's move to Paris is showing no signs of abating with Bartomeu's latest outburst. It is abundantly clear that emotions are still running very high at Barcelona following the Brazilian's dramatic exit, but it's difficult to see what good this public row is doing either party.
For Neymar, he would be best off ignoring this new accusation from the Barcelona president. In a week when he is already dominating the headlines for the wrong reasons following his trio of petty spats with team-mate Edinson Cavani – two on the pitch, one reported to have taken place in the PSG dressing room – it would not do him any favours to continue this pointless row with his former club.
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