MONTMELO, SPAIN (AFP) - Toto Wolff, the Mercedes Formula 1 CEO, explained on Monday (Feb 18) why Brexit would do untold damage to the F1 industry in Britain, calling it the "the mother of all messes".

"Brexit is a major concern for all of us that live in the UK and operate out of the UK," Wolff said at Montmelo where Formula 1 pre-season testing began on Monday.

The Mercedes team is based in Northamptonshire, while Red Bull is based in Milton Keynes and Buckinghamshire.

"Formula 1 teams travel to races at least 21 times a year, we are moving in and out of the UK, our people move in and out of the UK," he added, in reference to customs delays that could be incurred by The United Kingdom's exit from the European Union.

He was also concerned about customs for motor parts.

"The way we get parts and services is just in time at the last minute ... taxes would massively damage the Formula 1 industry in the UK," he said.

Visa and right to work concerns were also high on Wolff's worry list, thanks to the "26 nationalities in our team".

Wolff said there were no doubts in his mend that "No deal Brexit" or Brexit would be "damaging to what for me is one of the outstanding industries in the UK".

He explained: "Formula 1 feels like very much exposed to the decisions that could be made at a political level and it is a risk for our people and a risk for our industry."