Jul.24 (GMM) Bernie Ecclestone has played down suggestions the F1 calendar could blow out to an unprecedented 22 races in 2014.
The reports, including in the Italian magazine Autosprint, followed this week's surprise news that Austria will stage a Grand Prix next year, after a ten-year absence.
There are 19 races on the 2013 schedule, with Russia and New Jersey also scheduled to join next year.
But O Estado de S.Paulo correspondent Livio Oricchio said the prospect of a much longer calendar is "something that greatly concerns" F1 team bosses.
"The issue will surely be discussed at the Hungaroring in the coming days," he added.
That discussion, however, may no longer be necessary, in the wake of F1 chief executive Ecclestone's comments on Wednesday.
He told Austria's Kleine Zeitung newspaper: "We will have 20 races (next year), Austria included.
"Everything else I don't know -- please ask me again after the summer."
Mercedes chairman Niki Lauda said he suspects New Jersey will not take place in 2014.
"It didn't happen this year, because of a lack of money," he told the ORF broadcaster.
"As far as I know, it's already gone from the calendar," added Lauda.