The EU is facing embarrassment over claims that its new Europa headquarters, also known as the Space Egg building, was built with the help of undocumented migrant workers who at times went without pay.
The European council building in Brussels, which contains an ovoid glass structure, was opened in 2016 at a cost of £300m.
At its unveiling it was said to symbolise all that is best about the union. But EU officials are now facing claims from the Belgian newspaper De Standaard about the business practice of subcontractors who worked on the project.
One subcontractor, known as Group Diamond Services, which was subsequently declared bankrupt in 2015, was investigated by prosecutors after claims by Bulgarian workers, the paper reports. The men claimed to have gone without pay.
The investigation was closed in October because of insufficient evidence, but De Standaard found that in reality the file had been lost by prosecutors at some point in the four years since the inquiry started.
The paper carries interviews with some of the workers, including Beyhan Dzhelilov, 43, who was the head of a team of eight iron casters on the Europa building project.
He told the paper: “Several team members did not have Belgian residence papers. None of us got a contract, we were not insured.”
The main companies, Interbuild and Jan De Nul, who won the tender for construction of the Europa building, told De Standaard they were unaware of any exploitation of workers by subcontractors.
A spokesman for Jan De Nul told the paper that GDS was taken off the project early as the company “did not comply with contractual planning and technically did not perform the work correctly”.
The spokesman added: “Every employee from all subcontractors was checked for possession of the necessary documents. This also applied to the employees of subcontractors who acted on behalf of a subcontractor or a sub-subcontractor.
“Only after this preliminary inspection did the approved employees of subcontractors gain access to the site. For that they received a personal badge with passport photo. The yard was completely closed off from the area and only had two access gates with a badge system. Unauthorised persons could not enter the yard.”
The Council of the European Union has been contacted for comment.
An EU official working at the council said the Belgian state was the prime contractor for the Europa building.
He added: “The Council itself has not been informed by the Régie des bâtiments [the building regulations office] of any issues related to the working conditions of their contractors or sub-contractors
“All building and maintenance contracts undertaken directly by the Council are in line with the Belgian labor legislation.”