Frank Westerman, the union official who handled the major projects agreement on behalf of electricians at Heathrow Terminal 5, is to retire from the Unite union.

Westerman, who has been a union official for 25 years, had been London regional officer with Amicus, which merged with the T&G last year to create Unite. He had continued in his role in the expanded organisation, but is believed to have applied for redundancy in the wake of the merger.

It has also emerged that Steve Brawley, an Electrical Contractors Association official who was secretary of the major projects agreement forum, is to become chief executive of wage and conditions body the Joint Industry Board next month. A replacement has not yet been appointed.

As well as being instrumental in running the major project agreement at T5, Westerman was involved in industrial relations on the much delayed Wembley stadium project. He brokered a deal with Multiplex in June 2005 under which steelworkers would meet certain project milestones at certain times. This later became the basis of the revised schedule for the project.

In March 2007, 2 million members of Amicus and the T&G voted to create Unite. It is believed that Westerman applied for redundancy. One union source said: “I think there was always going to be the option for him to go – he’d been an officer for a very long time.”