LAING O'Rourke bosses were trying to head off three more days of strike action planned for Heathrow's T5 next week as Construction News went to press.
More than 900 workers downed tools last Friday and this Monday in a long-running row over bonus payments, despite the general secretaries of the GMB, the TGWU and Ucatt agreeing a peace deal.
One site source said: 'The whole thing is descending into farce. The national officials recommended a settlement but they seem to have no control over the local officials.
'The vast majority of people want to accept the latest offer but a handful of militants are standing in their way.
'It makes no sense to lose another three days' pay.'