Despite Bernie Ecclestone's earlier intimations to the contrary, it emerged at Hockenheim that Mercedes is in fact still yet to agree to the terms of the new deal.
It is believed a major sticking point is that top rivals McLaren, Ferrari and Red Bull have all been offered places on F1's post-floatation board, but not Mercedes.
Indeed, in an interview with McLaren boss Whitmarsh posted on F1's official website, the transcript quotes the questioner as saying that only "three team members from Ferrari, Red Bull and McLaren" will be on the board.
"I don't think that it is a secret anymore that nine teams have signed the contract -- and I really hope that the silver team next door (Mercedes) will sign very shortly and it will be then that we will take up our board position," said Whitmarsh.
Another major hurdle to the finalisation of the 2013 Concorde is the fact that the FIA is also yet to sign up.
When asked about that, Whitmarsh answered: "Well, my fear is that at the moment the deal hasn't been done and therefore it adds some volatility to the situation.
"At times formula one has lost opportunities because of inner frictions."
The Briton did, however, admit that it would be "possible" for formula one to live without its current governing body.
"But I don't think it is a productive thing," added Whitmarsh.
Interestingly, Whitmarsh - the head of the now-fractured teams alliance FOTA - also revealed that teams are in fact not signing a single Concorde Agreement, but a swathe of "individual contracts".
"If we (McLaren) were not happy with our contract we wouldn't have signed it, so I am not complaining, but the danger is that if we all have individual contracts that is probably not aligning us and bringing us together," he said.
"It (the Concorde Agreement) has never been perfect, but it's a model that before we abandon it we should be very cautious. Why reinvent something if it functions?"