Formula One's commercial boss Sean Bratches has sent a warning to historic circuits such as Silverstone, reminding them that their position on the calendar is not essential for sport's long-term future.
Following an announcement on Wednesday that F1 will go racing in Vietnam from 2020, questions over the future of existing races have been raised. The contracts for Silverstone, Hockenheim, Monza, Barcelona and Mexico City are all due to expire at the end of the 2019 season, and Silverstone and Monza have made no secret of their desire to see a reduction in the sanctioning fees they pay F1.