URGENT action is needed to prevent one of King's Cross's most famous landmarks falling into ruin, say concerned local residents.

URGENT action is needed to prevent one of King's Cross's most famous landmarks falling into ruin, say concerned local residents.

The metal tower on top of the "Lighthouse block" - at the junction of Pentonville Road and Gray's Inn Road, King's Cross has become one of the area's most beloved features.

Theories about its origins include that it was an old fairground helter-skelter, that it marked the building below as an oyster restaurant, or that it was a mere architectural flourish.

But in recent months the listed building has looked increasingly forlorn - slowly falling to pieces and covered in graffiti.

Now gaps have begun to appear between the metal sheets that make up the tower, while the roof is deteriorating fast - raising fears it is on the verge of collapse.

Local resident and campaigner Stephan Schulte said: "It is a local landmark and, as such, it should be preserved. I am less keen on the building beneath it but the 'Lighthouse' is one of those local London things everyone remembers. If developers don't hurry up and renovate it, there may be no 'Lighthouse' to save."

William Perrin, who runs a King's Cross community website, said: "It is symbolic of the decay and neglect in this part of king's Cross. The developers need to pull their fingers out and make their intentions clear.

"Camden council has preservation orders they could use but they have not been very effective historically."

Councillor Paul Convery (Labour) said: "It is in a shocking condition. I am all for a mix of old and new in King's Cross, and this is a little bit of the old that really needs to be kept. It is a very distinctive bit of architecture and it is very important to retain it."

Developers have been put off renovating the building until now because it is built over old Tube lines which make it difficult to work on.

In addition, the gyratory system means there is nowhere for builders to drop off supplies, making the project problematic.

The building has recently sold by the company P & O to developers UK Real Estate.

Gary Brookes of P & O Estates said: "It is a listed building and it is well-known in King's Cross - it's one of those structures that you say 'I will meet you opposite the tower'. It is important that the new owners look after the tower."

A council spokesman said: "We have an interest in preserving the architectural heritage of the area for everyone, which is why we have had discussions with consultants to restore the 'Lighthouse' to its former glory.

"Each listed site presents its own challenges - in some cases it can take a long time to work through these complexities. We keep all the buildings on English Heritage's 'at risk list' under constant review and we will continue to monitor the condition of the 'Lighthouse' in line with this policy.