Clancy takes up the three-year position on 1 May when he will join Acas chair Sir Brendan Barber and 11 employer, employee and independent members appointed by the government to oversee the service’s strategic direction.

Commenting on his selection Clancy said: "I'm proud to be appointed to this role as it reflects Prospect’s profile and influence. I hope to contribute to the excellent work of Acas as it fits with the agenda that the union is pursuing on behalf of members.”

Clancy brings a wealth of experience in employment relations to the role. He has been Prospect general secretary since 2012, deputy general secretary for eight years previously and a full-time union officer since 1989.

He is a chartered member of the Chartered Institute for Personnel and Development; a board member of the National Skills Academy for Power; and has been an Employment Tribunal and then an Employment Appeal Tribunal member continuously since 1994.

Clancy has a BA Hons in Law (Liverpool); an MA in Industrial Relations (Warwick) and an MBA (Cranfield).

Welcoming him, Sir Brendan Barber said he was delighted with the appointment, adding: “His wealth of experience and skills in employment relations will be invaluable in our role as independent, impartial and trusted workplace experts.

"The council sets out Acas' strategic direction, policies and priorities. I look forward to working with Michael to maintain our reputation as Britain's leading advisory service on workplace relations."

Acas is an independent and impartial statutory body that provides free and impartial information and advice to employers and employees on all aspects of workplace relations and employment law.

It was created as a statutory body by the Employment Protection Act 1975, and aims to use better employment relations to improve workplace institutions and everyday working life.

Last year its advisers were involved in more than 41,000 individual cases and 858 collective conciliations.