The 2014 season is set to feature 21 races, with Austria and Mexico returning to the sport and Russia joining the circus.
For a second successive season, the proposed race in New Jersey was not included on the provisional calendar.
“I think 21 is tough,” said Whitmarsh.
“I’ve got no personal knowledge of New Jersey so I can’t comment on that. Will those 21 all happen? There’s lots of rumours and speculation in the paddock about whether they’ll all make it.”
“Ultimately I think Bernie [Ecclestone's] job is to go out there and put the calendar together. I think he sometimes has to speculate as to the viability or how realistic some of them are. It’s easy for us to jump and complain about the calendar.”
“I think he’s got to put it together and I think we should be grateful that in the last few years, from pretty difficult and challenging times, not only has he maintained a calendar but he’s been able to bring some new venues into the sport. New Jersey, of course, would be fantastic in my opinion, it would be great for the sport. If you then say who would you lose?”
“We’ve all got our personal favourites and our personal least favourites, but I think it would be very disrespectful to use this platform to voice those personal opinions. I think Bernie’s just got to work hard to make sure we’ve got a good calendar. He generally succeeds one way or another and I suspect he will next year.”