Bob Blackman, national secretary for construction at union Unite, has announced his retirement after 12 years in the job.

Blackman, who retires on 1 May, is responsible for the building, civil engineering, construction, thermal insulation, building materials and supplies area of the UK’s biggest union.

A former T&G national secretary, Blackman was recently instrumental in agreeing deals for workers on the Olympics and Crossrail projects after pay negotiations broke down with the Engineering Construction Industry Association (ECIA).

A replacement has not yet been appointed, but sources say Brian Boyd, national officer for aviation, is a favourite. An announcement will be made in the next few weeks.

One union member said: “Boyd has done a great job representing BA [British Airways] staff and we’ve heard that he will take on the construction sector.”

Derek Simpson, general secretary at Unite, is set to make an official announcement over the next few weeks.