The deal builds Amey’s capability in transport planning, transport modelling and traffic engineering in the UK.

It will also secure transport consultancy contracts across the UK, for key clients in central and local government as well as for the private sector.

All of TPi’s professionals will join Amey’s consultancy business, taking staff in the division to 2,300 – a 10-fold increase in six years.

Mel Ewell, chief executive of Amey said: “With transport budgets under increasing pressure, it has never been more important for Amey to deliver value throughout the life cycle of our projects.

“By acquiring this highly respected consultancy, Amey is investing in some of the best professionals from within industry who will deliver the best long-term solutions for our customers.”

Alan Bailes, Managing Director of Transportation Planning (International) Ltd, said: “Amey has identified a clear business case for combining its own experience in delivering complex transport schemes, with our expertise in undertaking specialist transport planning and traffic engineering projects.

“Both Amey and TPi believe that integrating the two businesses will deliver the best results for all parties including our clients.”

Last June Amey’s bought national rail consultancy of WYG (formerly White Young Green), when Amey acquired 100 additional skilled professionals as well as a series of key contracts across the country.

In addition, Amey and its joint venture partner Cespa (AmeyCespa), both wholly owned subsidiaries of Ferrovial, acquired the waste management business Donarbon.

The company is delivering a 28-year, £730 million waste management PFI contract in Cambridgeshire for Cambridgeshire County Council. It also has a wide range of waste treatment facilities.