The Spaniards are furious with Arsenal for trying to snatch 16-year-old wonderkid Jon Miquel Toral Harper from their academy — just like they did with Cesc Fabregas.
SunSport can reveal the storm erupted before the clubs clashed at the Emirates last Wednesday as Barca president Sandro Rosell made his opinions forcibly known to Gunners chief executive Ivan Gazidis.
An eye witness said: "Rosell seemed to be raising his voice at Gazidis who stayed calm and did not respond. It was clear, though, that Rosell was particularly angry."
The Catalan giants are furious with the Gunners for trying to lure midfielder Toral. He has an English mother and is, I understand, now close to signing a professional contract with the Gunners.
Ironically, he has already appeared in a Nike advert alongside Fabregas!
The bitter bust-up is now threatening to overshadow the return leg at the Nou Camp when Arsenal defend a 2-1 lead.
There is no suggestion the Gunners have done anything untoward but the Catalans are up in arms.
Rosell is particularly sensitive about this issue as he was vice-president when the Gunners nabbed Fabregas back in 2003.
The Barca president argued with then Gunners vice-chairman David Dein and secured a first-refusal option for Fabregas if Arsenal ever sold him.
Now he is livid with Arsenal over the new incident in which the Gunners seem to have gone behind Barcelona's backs again.
Barcelona have been publicly tapping-up Fabregas for several years and last summer he was on the verge of returning to his hometown club in a £31million transfer — but Gunners boss Arsene Wenger blocked the move.
Wenger has been angrily accusing Barcelona of underhand tactics in their attempts to snatch Cesc.
Now this latest incident is certain to further sour relations between the two clubs and is certain to spice up the second leg at the Nou Camp on March 8.
wenger forever only know how to say other people and never look at himself..
cant blame Barcelona for acting like this. Arsenal stole Fabregas from under their noses, esp when Barce spotted and spent untold resources for developing Fabregas. Barce may be feeling deja vu now. What if this boy turn out to be another Fabregas if Arsenal signed him
Anger: Barcelona president Sandro Rosell with manager Pep Guardiola
Arsenal have been accused of 'immoral' behaviour after poaching Barcelona whizkid Jon Miquel Toral Harper.
The Gunners have completed a £300,000 deal to bring the 16-year old midfielder from the Spanish giants' academy.
Toral, who has an English mother, follows in the footsteps of Arsenal captain Cesc Fabregas, who was also lured from Barca at a young age.
Previous deal: Cesc Fabregas
But the north London club have been criticised by Barcelona president Sandro Rosell after completing their latest move.
He said: 'It's very important to keep this group of young lads together with a grounding in our way of playing football.
'We don't like it when other clubs come with offers of money just before the player's 16th birthday. It's legal but a little immoral.'
Rosell was also asked whether Barca will make another effort to bring Fabregas back to the club during the summer.
The 23-year-old Spain international is seen as an eventual replacement for playmaker Xavi, who turned 31 in January.
Rosell added: 'Barca must have the best possible team and we have to fulfil the requests from the technical staff without forgetting the economic situation and that Barca has to pay salaries and costs.
'If Cesc comes, because the technical staff want him and he wants to, the club members would accept it.'