Extensive tests with the trains using cameras mounted beneath them revealed accumulations of snow under the trains which froze and then fell-off damaging and dislodging several components, which dropped onto the track.

AnsaldoBreda, Italy, which has so far delivered nine of the 19 trains ordered, has assembled a team of 40 engineers in an effort to resolve the problem. The company has acknowledged the cause of the problem and issued a public apology via Twitter on January 19. "The Fyra trains have been properly and duly tested and verified," says Mr Alessio De Sio, AnsaldoBreda's senior vice-president, external and institutional relations. "They performed tests in the climate chamber at the Rail Tec Arsenal facility in Vienna as well as development and verification trials on the test circuit at Velim in the Czech Republic and on the Fyra line, and in no way did the problems outlined above occur."

SNCB has told AnsaldoBreda it will cancel its contract for the trains unless the problems are resolved within three months.

The Dutch secretary of state for infrastructure, Mrs Wilma Mansfeld, has demanded to see plans by the end of the month for a replacement service as the V250 trains could remain out of service for the foreseeable future. Netherlands Railways (NS) has asked the Dutch infrastructure manager ProRail to identify paths to allow a conventional inter-city service to be reinstated between Amsterdam and Roosendaal, while SNCB has announced it will launch an interim Roosendaal - Antwerp inter-city service.

In the meantime, passengers have the option of using the more-expensive and less-frequent Thalys high-speed services, or making do with a mixture of local trains or a temporary bus connection between Breda and Antwerp.