Tube's £500m moving ads delayed

A £500m deal to install moving-image billboards on London Underground platforms has run into problems. XTP, a cross-track projection system, is designed to beam adverts on to curved screens on walls opposite platforms, allowing adverts to change every few minutes.

LU announced the project with much fanfare a year ago and said the first screens would be working in spring this year. But none has appeared and no new launch date has been given. Industry sources claimed the project had been shelved because of technical problems due to equipment overheating in the sealed units that are required by fire regulations.

But LU denied this. A company spokeswoman said trials had gone well and there were no technical difficulties with XTP, which is already used overseas. She added: 'There has been a delay due to one of the partners and we do not yet have a launch date. But we want this to go ahead and we will find new partners if necessary.'

One of LU's existing partners is Swedish group DHJ Media, which has the patent for the XTP technology. DHJ, which specialises in real-time advertising systems, lost £4m in 2000 and postponed a planned listing on the Swedish stock market last year.

The Tube is in the process of being partly privatised and XTP would give it a useful-earnings stream on top of traditional advertising income. When the deal was announced last year, it was anticipated that 400 XTP screens across the Tube's network of 260 stations could generate £500m over the 12-year life of the contract.