The Cardiff Millennium Stadium's innovative retractable roof has developed a fault three weeks before the venue is due to host the FA Cup final on 12 May.
A spokesperson for the stadium said: "The stadium's retractable roof is temporarily out of action because of a technical fault. Expert engineers have been called in to rectify the problem and work is to commence this week." An insider said he believed the problem was caused by a wheel that had come off a roof rail, causing the roof to stick. He said it would be up and running shortly.

This week, an emergency meeting of all of the project's engineers was called, so the stadium manager could assure the Football Association that the stadium would be ready for the final.

A source at WS Atkins, engineering consultant on the stadium, said the meeting had been called to make sure the problem could be pinpointed and solved as quickly as possible.

A spokesperson for stadium contractor Laing said: "We are currently working with the engineers on the project in helping to find a solution to the problem of the roof." The £112m stadium will also have new turf laid for the final. The FA made it clear that it was unhappy with the state of the pitch, which was relaid in late January before the Worthington Cup final.

Now the stadium will have to pay £100,000 to put down another surface after pitch experts decided that it was not good enough for the Liverpool-Arsenal clash.

The FA is concerned not only about the players performing on a poor pitch but also projecting the right image for a final that will be watched by 40 million viewers in 20 countries.