A draft 2014 calendar circulated to team bosses at Monza on Thursday features an unprecedented 21 races.
The provisional schedule, seen by media outlets including the British broadcasters Sky and the BBC, and the news agency Reuters, includes new grands prix in Russia, Austria and Mexico.
New Jersey and India are missing, but other races that have also appeared uncertain recently - notably Korea - are listed, taking the count beyond the 20 dates that has been regarded by team bosses as the maximum.
"It remains to be seen which one is dropped," an unnamed team boss told Reuters on Thursday.
Korea, Russia and Mexico - with its race slated to be held on the ageing scene of the 1992 grand prix in Mexico City - are all listed as subject to confirmation of the venue or contract.
The World Motor Sport Council will consider the draft calendar at a meeting in Croatia later this month.
Draft 2014 calendar
16 March: Australia (Melbourne)
23 March: Malaysia (Sepang)
6 April: China (Shanghai)
13 April: Korea (Korea International Circuit)*
27 April: Bahrain (Sakhir)
11 May: Spain (Barcelona)
25 May: Monaco (Monaco)
8 June: Canada (Montreal)
22 June: Austria (Red Bull Ring)
6 July: Britain (Silverstone)
20 July: Germany (Hockenheim)
27 July: Hungary (Budapest)
24 August: Belgium (Spa-Francorchamps)
7 September: Italy (Monza)
21 September: Singapore (Marina Bay)
5 October: Japan (Suzuka)
19 October: Russia (Sochi)*
26 October: Abu Dhabi (Yas Marina)
9 November: Mexico (Mexico City)*
16 November: USA (Austin)
30 November: Brazil (Interlagos)
*subject to confirmation