Renault Sport Managing Director Cyril Abiteboul has accused Mercedes of "blocking the system" by implementing excessive periods of gardening leave on staff that leave the  Brackley-based outfit for other teams.

The issue has become a hot topic in recent weeks after the French manufacturer, who are still building their workforce at Enstone after returning to Formula 1 as a works team in 2016, announced the controversial appointment of Marcin Budkowski last month.

Budkowski is set to join as early as January after leaving his position as Technical Chief at the FIA prior to the Malaysian Grand Prix, but due to his vast knowledge of not only this year's cars but also early plans some have for 2018 several top teams, including Mercedes, want that period extended.

Though Abiteboul's comments were not directly related to Budkowski and more to signing engineers in general, the Frenchman singled out Mercedes when talking about the process of bringing new members to the team.

“Red Bull is not too aggressive in the way they are keeping their people, but Mercedes are the most aggressive,” he claimed. “We signed up a senior person from Mercedes last year, and he is not due to join before 2019 because of the contractual situation.

“The UK is very favourable to protect employees for the benefit of the employer, but that is giving us a bit of a hard time," Abiteboul added. “We know it, so we simply have to deal with it."

Though it is understandable a team such a Mercedes wouldn't want their secrets, which have cost a lot of money and time to develop, to end up benefiting a rival, the Renault boss also suggested that the prolonged period a member of staff has to wait before assuming his new position is detrimental to the sport when top teams already have significant advantages elsewhere.

“Red Bull are not stupid in the way they are protecting their staff. Mercedes have the right to do what they are doing, but I think it is a bit unfair," he said. “They already have the financial resources but now they are blocking the system by making sure no one can go anywhere.

“It is still a sport and we need to provide a good show and interesting show and that is not what is happening if you are doing that.”