An Arup spokesperson refused to be drawn on when the tests would be complete or when the bridge was likely to be reopened.
The spokesperson said: “There will be a thorough analysis of the results, so it is difficult to say when the bridge will be ready. Obviously we want it reopened as soon as possible.”
The company denied rumours that it had used hundreds of employees in a secret test of the bridge. “It would be hard to keep any test on the Millennium Bridge a secret,” said the spokesperson.
The bridge was closed shortly after it opened in 2000 when the problem wobble was discovered.