Messi will be worlds best paid - Barca president
The four-time World Player of the Year has a contract with the Catalan giants until 2018, but Bartomeu said talks were on-going with the player's father and principal agent Jorge Horacio Messi over a deal that would surpass the five-year contract Cristiano Ronaldo signed with Real Madrid in September last year.
"We are in the midst of the season, so it is not the moment to be negotiating with him, but it is the moment to talk to the agents and with his father and that is what we are doing," Bartomeu said in an exclusive interview with AFP sports.
"We will talk with them about how we see the player. He is our star and he has a contract until 2018 because we want him to participate in our future, but there is the will within the club that he becomes the best paid player in the world.
"He is the number one and, as we have said various times, he also deserves to be the best paid player in the world."
Messi had been plagued by muscular injuries early in the season, but has recently returned to top-form as he has scored a hat-trick in consecutive games, most recently, in Sunday's thrilling 4-3 win away to Real Madrid.
After scoring the winner with his third goal of the night seven minutes from time at the Bernabeu, Messi kissed the Barca badge on his shirt several times in an uncharacteristic show of exuberance.
And contrary to some rumours linking him with a move to free-spending Paris Saint-Germain or Manchester City, Bartomeu is convinced that Messi is determined to remain at Barca for many years to come.
"Here there is no doubt. Leo Messi arrived here as a 13-year-old and is now 26, soon to be 27. You see how he plays, he is a decisive player and has led all the success Barca has had over the past few years. That is why he has a contract until 2018 and there are no disagreements.
"There is only an enormous desire, both from the player and the club to reach an agreement. We will get there and we will get there calmly.
"We are sure we will reach a deal with Messi, we are convinced because it is his wish too. He said so just a few days ago. We will have Leo Messi at Barcelona for many years to come."
Bartomeu also stressed that it is the board's wish that manager Gerardo Martino sees out his contract until 2015 at the very least.
Martino has endured an up and down first season in charge of Barca, but the Spanish champions are still fighting for titles on three fronts.
"We are very happy with him, he is a person that is giving all the right signals, messages and acting in a manner that fits in perfectly with what we want FC Barcelona to be. He knows we are happy with him and the decision on whether to continue will be his.
"He has a contract until 2015, but at the moment there are so many important games that are left to play that is what he is concentrating on."
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