MARRAKESH, Morocco - Mexican Sergio Perez needs to gain more experience before any move to Ferrari can become a realistic proposition.So, at least, says the Italian Formula 1 team's president Luca di Montezemolo when questioned on the sidelines of a Financial Times luxury conference.Montezemolo added that it was too early for any decision on the future of Ferrari's under-performing Brazilian Felipe Massa and spoke out also against any expansion of the calendar beyond the current 20 races.SWOP FOR MASSA?"We never take a decision before the second half of the season," he said of Massa, who has scored only 10 points from six races while Spanish team mate Fernando Alonso is leading the championship on 76.Perez, who drives for Ferrari-powered Sauber and finished a close second to Alonso in Malaysia in March 2012, is already part of Ferrari's young-driver programme and has been seen as a possible replacement for Massa despite being in only his second full F1 season.Montezemolo played down the 22-year-old's immediate prospects: "Perez is a good driver but to drive a Ferrari you need more experience. He is one of the potential best young drivers for the future but before putting a young driver in a Ferrari I need more experience and more results."MASSA NEEDS TO BE BETTERMontezemolo said Massa, who has been at Ferrari since 2006 and was runner-up in the championship in 2008 before suffering a serious head injury in 2009, had yet to be ruled out of the picture. He is contracted to Ferrari until the end of the 2012 season. "I'm sure that, because we are improving our car, the car will be less difficult to drive," he added, “and I expect from Felipe better performances as I have already seen in Monte Carlo, because in Monte Carlo he was among the five quickest drivers on the track and in the qualifiers."I hope he will continue like this. We are not taking any decision yet for the future - it is too early."Next Sunday’s (June 10) 2012 Canadian F1 GP in Montreal will be the seventh round of what is now a 20-race championship.OTHER RACES LINED UPA research note this week from UBS, one of the joint global co-ordinators of F1's now stalled $3-billion planned IPO in Singapore, spoke of an expectation that the number of races would rise to 22 by 2015. A (first) Russian GP is already scheduled for Sochi in 2014 and a new race in New Jersey, with the New York skyline as a backdrop, is due in 2012.France is also eager to return, but alternating annually with Belgium.F1 rights-holder Bernie Ecclestone told Reuters this week that he was also negotiating for an eventual Mexican GP and a return to Argentina has also been mooted.Montezemolo declared any expansion beyond 20 would not be a good idea: "There are too many - we have to discuss it. I will be totally against increasing the number of races. Twenty is the super maximum possibility. I will not be prepared to accept more than 20."