Barcelona president Sandro Rosell has said he is annoyed that Manchester City have tried to use "privileged information" to tempt current Barcelona players and staff to Eastlands.
Premier League champions City, whose director general is former Barca vice-president Ferran Soriano, have been linked with moves for Barca players including David Villa, Sergio Busquets and Cesc Fabregas, as well as a number of the Catalan club's backroom staff - although City have denied any such moves in the past.
Taking advantage of knowledge learnt at a previous club went against the accepted rules of behaviour within football, Rosell suggested to Catalan radio station RAC1 on Monday evening.
"There have been offensives from City, at all levels of the club, but nobody wanted to go," Rosell said. "We do not give them any importance, because it has not just happened with City. It does annoy me that people who have worked for the club use privileged information, obtained when they were at Barca, for another team. Things should be cleaner and more professional."
Rosell said that neither Villa, who has been regularly linked with a move to the Premier league, nor any other player would leave Barcelona this January, but appeared to suggest the situation could change next summer.
"(Villa) is not going to be loaned or sold in the winter transfer window," he said. "He is just as untouchable as Thiago, Lionel Messi, Alexander Song or Jordi Alba. We want all our players until the end of the season. Next year? We will talk then. Now I would say he will stay. It is not easy to get into this team. Who do you leave out to play Villa?"
The former Nike executive said he was confident blaugrana goalkeeper Victor Valdes, who has hinted recently he would not mind playing abroad at some point, would extend his current contract, which ends in June 2014.
"He will be another of the group of magnificent players we have and we want him to stay at home," Rosell said. "We are not looking for any replacement. I hope that when (Barca sporting director Andoni) Zubizarreta meets with them they reach an agreement."
Rosell, who suggested the naming rights to a proposed new Camp Nou could be sold if the economic situation required it, said he was not particularly looking forward to seeing former Barca boss Josep Guardiola coaching elsewhere in the future.
"It will feel strange but we will have to get used to it," he said. "Pep is a professional and he will be a Barca fan all his life. If we play the team he is coaching, it will not be too much fun."
Meanwhile, current Barca boss Tito Vilanova is likely to shuffle his pack for Wednesday's Copa del Rey quarter-final first leg at home to Malaga.
While Villa remains sidelined with the thigh problem which saw him miss Barca's 3-1 Primera Division win between the teams on Saturday, Jose Pinto, Martin Montoya, Alexis Sanchez, Thiago, Alex Song and Adriano Correia could all come into the starting line-up, with Xavi Hernandez, Sergio Busquets, Dani Alves, Jordi Alba and Pedro Rodriguez among those tipped to be given a rest.