Race promoter Francois Dumontier said he had no choice other than to postpone June's Canadian GP.
As F1 decides to extend the current three-week factory shutdown for a further fortnight, the Montreal organizers announced officially that they are "saddened" to call off the popular race at the Circuit Gilles Villeneuve for now.
"Closing Canada's borders was one thing, but we thought it could move in the right direction," Dumontier told Le Journal de Montreal.
"That was not the case.
"We gave ourselves until Easter to make the decision, but as soon as premier Francois Legault announced that Quebec was on hiatus until May 4, it was clear that this was jeopardizing the organisation of our race," he added.
"The erection of temporary infrastructure was to start well before this deadline. But I am calm. I now pass the baton to the officials of the grand prix de France."
Indeed, the French GP at Paul Ricard is now nominally scheduled as the effective season opener at the end of June.
Dumontier said: "The calendar as we know it today, after all of these postponements – it must be forgotten. I even think that between 15 and 18 races, as F1 wants to do, is an optimistic forecast."
He does not even rule out that Canada could in reality be the first race of 2020, much later in the year.
"Because of our climate, our grand prix will have to take place before mid October. But yes, anything is possible," said Dumontier.