Mercedes Formula 1 boss Toto Wolff says a no-deal Brexit would be "a nightmare scenario" for British-based teams.
Wolff said the United Kingdom leaving the European Union without a deal would be a "massive advantage" to EU-based teams such as Ferrari and Alfa Romeo.
Eight of the 10 F1 teams have bases in the south-east of England.
"A no-deal Brexit would have a major impact on our operations going to races and developing cars," Wolff told BBC Sport.
Wolff says the Mercedes team, who rely on ease of movement for the supply of their parts, are already considering other options for their equipment and staff following the withdrawal on 29 March.
"We have certain contingencies in place, like having more stock and thinking about how we would get parts and people in and out of the country," he added.
"But it would be a disruption and it would cause all the UK teams a lot of headache, while Ferrari in Italy and Sauber (Alfa Romeo) in Switzerland would have a massive advantage over every UK-based team."
Mercedes' F1 team is based in Brackley in Northamptonshire, and their F1 engine base 30 miles away in Brixworth.
Christian Horner, whose Red Bull team are based in Milton Keynes in Buckinghamshire, also said the political situation is of concern.
"Brexit consumes the news," he said. "As a team we do our due diligence, but whether there is a no-deal, any deal, we will have to deal with it, and life ultimately will go on.
"It is important we get to a conclusion sooner rather than later to get rid of all the uncertainty because it is unsettling for so many aspects.
"Brexit is something that really needs to be addressed for the clarity for everybody. It is very difficult to make plans without clarity."
The UK remains on course to leave on 29 March but Prime Minister Theresa May has been unable to convince a majority of MPs to back the withdrawal terms she struck with the EU.
Business Minister Richard Harrington said on Sunday he did not think Mrs May would let Britain leave without a deal.