IT has been hailed as both an "imaginative beacon" that will put Southampton on the map and branded as "light pollution" that would be "an infringement of personal liberty" for nearby residents.

As city councillors delay plans for the Southampton Laser Gateway to permit trials in the autumn, the debate over the £249,000 project to shine four green lasers from the Civic Centre clock tower looks set to beam on.

But despite concerns from astronomers and environmental groups over the scheme, which would see the 2.7mm beams stretch up to 14 miles in a north, south, east and westerly direction, a similar project has been in place elsewhere in the UK for nearly a decade.

South of the River Thames and at the heart of one of London's oldest parks, the Royal Observatory in Greenwich is home to a popular laser project.

At the home of the international timeline, the thin beam of light follows the Prime Meridian line and splits the earth into Eastern and Western Hemispheres.

Installed eight years ago to mark the turning of the Millennium, the Prime Meridian laser marks the line of 0 degrees longitude from the top of the Royal Observatory - which hails a stunning night time view of London from the natural surroundings of Greenwich Park.

Welcome Local resident Ann Hutchinson of the Friends of Greenwich Park said the green laser from the Royal Observatory was seen as a welcome addition to the night sky.

"I have never met anyone who has been unhappy about it," she said.

Situated on a hill near the centre of the park, the laser beam shines down from the Royal Observatory near the neighbouring National Maritime Museum and Queen's House attractions towards the River Thames.

When dark enough the pencil thin line of light slices through the staggering view of London's Canary Wharf buildings for some ten miles and disappears in the direction of the eye-catching iconic landmark of the Millennium Dome.

"Greenwich Park is the oldest of the Royal Parks and the laser is fairly recent," said Mrs Hutchinson.

"It follows the Meridian Line and is very visible at night time so if you are going along Romney Road in front of the Queen's House and look up, you can see the Meridian."

"It is just a sign of Greenwich, people see it and say there's the Meridian Line'.

"I think it's wonderful," she added.

Designed by US company Spectre Physics, the bright green single beam comes from a diode laser which is reflected off two mirrors and comes out of a hole in the old observatory building, seven metres above the precise location from where time is measured.

On a clear night it can be visible for more than ten miles and on a cloudy night it can be seen even further away as the lights reflect off dust and cloud particles in the atmosphere.

Mrs Hutchinson, a former local councillor who is also Chair of the Wildlife Group for Greenwich Park, said the laser had never been a problem for the animals and creatures that inhabit the area, and that people who live nearby found it to be a popular addition to the park.

"There really is no problem with it," she said.

"People who live nearby are quite happy about it. They are very happy to have the Meridian Line - it is not too obtrusive, it is very visible and it is what Greenwich is all about. So people are very happy to have it as their neighbour."

Local Councillor David Grant, who represents the Greenwich West ward where the Royal Observatory lies, said the laser beam had never been an issue for residents.

"I have been a councillor here for the past ten years and I have lived in Greenwich for 30 years and I never found anybody to have a problem with it," he said.

"It is just a single beam that heads down from the Observatory in the park and it is important to note that it was not the council that put the laser up, it would have been the National Maritime Museum and the Royal Observatory which it beams from.

"I think the only time people may have mentioned it is when they may be passing it or see it in the night sky.

"There has certainly not been any concerns from anyone and it really isn't an issue," he said.

In Hampshire councillors in all proposed directions of the lasers have been divided on the scheme, which was originally hoped to be launched as part of Southampton's 95th commemorations of the sinking of Titanic in early April.

In Eastleigh, council leader Keith House has given his backing to the scheme, deeming it as a "beacon for the city and its region".

But New Forest Council has raised concerns alongside Chilworth Parish Council whilst further afield towards Portsmouth local councillors in Denmead, said they would oppose any plans that could result in light pollution.

Southampton City Council is now set to carry out a series of trials for the laser gateway project in the autumn when the skies become darker.

As part of the trials they are expected to carry out tests with a range of beams and different, renewable energy sources.

However the delay in approving the project could mean the council loses funding from the South East England Development Agency - SEEDA - which was due to pay £250,000 for the project, and which has to be used by March.