The much-heralded opening of Bradford's only permanent tribute to the Millennium - a £4 million visitor attraction - has been delayed by a single pane of glass.

The Life Force centre was due to open its doors this week after much publicity trumpeting its opening date, but now faces keeping its doors firmly shut for a further month - because of an exploding pane of specialist glass.

A national celebration of different faiths and Bradford's past and present, the state-of-the art centre - mainly funded by the Millennium Commission through National Lottery cash - was expected to attract thousands of visitors to the district after it opened on Thursday.

But construction of the city centre museum was delayed because of the glass exploding in manufacture in Belgium.

The heat-proof glass costs £150,000 to manufacture and was to be used on a dramatic walkway linking the Life Force Centre in historic St Peter's House, the old Post Office at Forster Square, with the Cathedral.

But the manufacturing calamity meant the glass had to be created from scratch - leaving the centre's bosses with no option but to keep the doors firmly shut - for the time being at least.

The walkway will house a restaurant, billed as a rival for some of London's top eating houses, as well as offering stunning views of the Cathedral and the city.

But without the specialist reflective glass - manufactured only by Pilkington's in Belgium and Austria - Life Force Centre bosses feared visitors would fry in the heat.

Spokesman for the project Sue Coffey said: "It couldn't be done using ordinary glass because people dining would have simply fried in the heat."

She said the glass - which was ordered from specialists in Belgium by contractors P S Turner (Construction) Ltd - had a special coating which deflected the heat.

Stan Brown, contracts manager for Turners, said the glass cost £150,000 and could only be obtained at Pilkington's, Belgium and Austria.

He said: "It is a very high-tech process and very specialist. But unfortunately it exploded during the process and it can take weeks to replace."

The glass has now been installed and finishing touches are being made to the bridge and building.

The modern centre explores faiths and beliefs from all cultures, through state of the art exhibitions and projects.

There will also be celebrations of the world's main religious festivals.

Facilities will include a herb and spice cookery school with courses, demonstrations, talks and lectures. It also offers a hospitality venue for conferences and business meetings in the Clock Tower at St Peter's House.

The centre has been developed through a Millennium Lottery award and is expected to attract visitors from across the world.

A Millennium Lottery spokesman said today: "We are aware there is a small delay which is outside the control of the project. We look forward to its opening in July."