Workers helping build the new Wembley Stadium have been laid off over a pay row with contractors.
The stadium's construction has been beset by problems
Union officials said steelworkers, scaffolders and welders were given notice they would no longer be employed as of next Tuesday.
The 120 lay-offs, the latest problem to hit the new £757m stadium, are because sub-contractors have not been paid.
Last week work stopped for a day after a 50-tonne steel rafter fell from the roof of the stadium.
The GMB union said its members had been told they were being laid off because there was not enough money to pay wages.
National officer Tom Kelly said: "We have instructed our members to carry on working normally until we have an opportunity to resolve the matter.
"The stadium is not finished and someone will have to employ our members to finish the job."
Frank Westerman, of Amicus, said he had also advised the union's members to continue working "normally" while negotiations continued.
The construction company, Multiplex, issued a statement saying: "This is an issue between Hollandia and Fast Track Services.
"We're looking to Hollandia for continuity of work and we've just met with the shop stewards who have given Multiplex assurances that they will continue to work while Hollandia discusses the issues with Fast Track Services."
Last week, Multiplex also said work to repair underground sewer pipes would not affect the completion deadline for the stadium.
Pipes running beneath the 90,000-seater arena in north-west London have buckled due to ground movement.
Multiplex is due to give an update on the progress of the project.