A trial has begun in Victoria's Supreme Court after World Touring Melbourne brought civil action against the Australian Grand Prix Corporation over the cancellation.

The promoters want the grand prix to fork out $8.7 million in damages.

Then-Australian Grand Prix chief executive Andrew Westacott told the promoters he'd received a "blanket directive" from Victoria's chief health officer Brett Sutton to cancel both events, in a phone call played to the court.

"In the global scheme of all the events, it's sadly the decision based on all the cards we're all being dealt with," Mr Westacott said on the call.

"It's just one of those unfortunate things we have to deal, and move on with."

World Touring's barrister Nicholas de Young KC said evidence showed the health advice was a recommendation and not a directive, and alleged the grand prix had misled promoters and withheld information about Mr Sutton's views.

"The plaintiff would have run the concert had they known the true position," he told the court on Monday.

Mr de Young said mass gatherings were prohibited in Victoria from the following Monday.

He said World Touring lost $8.45 million due to the cancellation, after paying back $2.4 million in ticket sales and losing further revenue from predicted merchandise, food and drink sales, as well as sponsorship and TV and film content.

Barrister Gerard Dalton KC, acting for the grand prix, denied it had misled promoters or that Mr Westacott had misrepresented Mr Sutton's advice.

Further, he said that was "irrelevant" as the concert would have been cancelled by the CEO either way.

"It doesn't matter if he misrepresented the CHO's advice by saying it was a direction when in fact, it was a recommendation," Mr Dalton said.

"What matters is, would the concert have gone ahead?

"The concert did not go ahead because Mr Westacott decided that it could not go ahead, in light of the advice that he received from the chief health officer."

The trial before Justice Clyde Croft continues.