Lionel Messi is fascinated by Manchester City and often asks Pablo Zabaleta about life at the club, according to the Argentina right-back who numbers the world player of the year as a close friend.

Messi's future at Camp Nou has been the subject of speculation after Barcelona's president, Sandro Rosell, was forced to deny that Cristiano Ronaldo's new five-year deal worth €17m (£14m) a year had moved the Argentinian – who has a €250m (£208m) release clause and earns €16m a year – to demand a review of his current agreement, which ends in 2016.

Zabaleta, who joined City in 2008 from Espanyol, said: "I remember when we were in Barcelona we were very close friends because we were living in the same city and had known each other for a number of years. I was just starting out at Espanyol and Lionel was at Barça. When I signed for City I think two days later the news broke that Sheikh Mansour had bought the club and Lionel always recalls that I joined at such a fantastic time.

"He asked me a lot about City but I couldn't tell him much because I didn't know much myself – but it's something we often talk about. Plus the fact that I'm still here."

City's passage to the Champions League knockout stage is already secured, and despite the Catalan club's recent record in the competition, winning it three times in the last eight years, Zabaleta would relish a tie against Barcelona.

"If we have to face Barça in the Champions League, we will be ready and I think it will be a fantastic game – but we'll wait and see. I played against Messi for Espanyol against Barça and I recall in my second season at City when we played in the Nou Camp in the Joan Gamper Trophy and we won 1-0 with a goal from Martin Petrov," he said. "So I think we are about level at the moment."

Zabaleta also played down the prospects of him claiming a Premier League, Champions League and World Cup treble this season. "I don't know, the good thing is we are in the race for all those trophies and as a player you have to try and win everything you are involved in," he said.

"There are differences between each competition, of course. The Premier League is over 38 games while the Champions League and World Cup is over fewer games and anything can happen. From my own experience, winning the Premier League was so special because it means everything to the players and the supporters and it is the biggest prize in England.

"As for the Champions League, we are up against the best teams in Europe and it is a difficult competition to win being realistic. But we will try our best and you never know in football."