The controversial statue of disabled artist Alison Lapper was officially unveiled yesterday on Trafalgar Square's fourth plinth.

Marc Quinn's 13-tonne, 11ft 6in high white marble sculpture is London's latest landmark.

Ms Lapper, from Shoreham, who was born with no arms and shortened legs due to a congenital disorder, posed naked for Quinn when she was eight months pregnant.

London Mayor Ken Livingstone hailed her as a "modern heroine". He said the statue, titled Alison Lapper Pregnant, made a worthy companion to Nelson's Column.

He said: "This square celebrates the courage of men in battle. Alison's life is a struggle to overcome much greater difficulties than many of the men we celebrate and commemorate here.

"Alison Lapper Pregnant is a modern heroine - strong, formidable and full of hope. It is a great artwork for London and for the world."

The artist and his subject attended the unveiling.

Ms Lapper, there with her five-year-old son Parys, said: "This is an amazing day for me, not only just for me but for all the people in the country and across the world who have got a disability. It's a really positive sculpture and an important step forward. We have been hidden away for way too long. It's about time people started to confront their prejudice.

"It's a real honour to be up there."

Mr Quinn said: "I regard it as a modern tribute to femininity, disability and motherhood. It is so rare to see disability in everyday life, let alone naked, pregnant and proud."

Mr Quinn's work was chosen from a shortlist of six. It will remain in the square for 18 months.

The statue divided public opinion amongst visitors to Trafalgar Square.

Nicola Webb, 17, a student from Walthamstow, east London, said: "It's a nice sculpture, it's quite personal. I like the fact she's naked because she's saying: 'This is who I am.'

"And it's about time there was a statue of a woman here."

Molly Sinclair, 77, from Streatham, south London, said: "I don't see why a disabled person shouldn't be here, we all have to think about these things, don't we?"

But Philip Brannon, 63, from Croydon, south London, said: "Everyone is looking at it saying they think it's wonderful but it's the Emperor's New Clothes.

"I don't object to having a disabled person up there and the statue itself is very well done, but who is she? They could have chosen someone much better who everyone has heard of."

Another onlooker, who declined to be named, said: "I know you're not supposed to say it these days but I don't want to look at something like that. I'm sure there's a place for a disabled statue but I don't think it's appropriate."

Don't miss our interview with Alison Lapper in Weekend, tomorrow.