An American landscape artist has won the competition to design a �3m fountain in memory of Diana, Princess of Wales.

Kathryn Gustafson's design, described as "restrained and elegant", incorporates a 50 x 80 metre oval stone ring filled with water to be built next to the Serpentine in Hyde Park, London.

	:	Diana's memorial
Click here for an enlarged image of the design

Work on the final design will begin almost immediately, with the fountain expected to be in place by the sixth anniversary of Diana's death in August 2003.

Her sons, Princes William and Harry, said: "We are glad that a decision has been taken on the design of the commemorative fountain to our mother and we are grateful to Rosa Monckton and the committee for all their hard work."

Here we have a woman who was one of the most celebrated Britons ... and we have remembered her with a puddle

Vivienne Parry, friend of Diana's

But the design has not found favour with everyone and there was some criticism expressed at Wednesday's unveiling.

Vivienne Parry, a friend of Diana's, said it was "disappointing".

"Here we have a woman who was one of the most celebrated Britons for the last quarter century and we have remembered her with a puddle," she said.

Culture Secretary Tessa Jowell stepped in earlier this month to make the final choice, after a committee of eight set up to oversee the project split 50-50 on the final shortlist of two, from more than 100 ideas.

Ms Jowell picked Miss Gustafson's work, said to be more traditional, over Bombay-based designer and former Turner Prize winner Anish Kapoor's 16ft dome of water.

Miss Gustafson is best known in Britain for her glasshouse at the National Botanic Garden of Wales.

The original committee, chaired by Diana's friend Rosa Monckton, had descended into bitter wrangling.

On announcing her decision, Ms Jowell said it had been "the judgment of Solomon".

The finalists were judged against an agreed set of five quality criteria, said a spokesman for the Department of Culture, Media and Sport.

Water will cascade down steps in the channel, which varies in width

He said the final decision was based on the committee's views of which team best met all the relevant criteria and Ms Jowell had not made a personal judgment about the quality of the bids.

Ms Jowell paid tribute to Rosa Monckton and her committee, saying they had performed "an enormously difficult task" with "great dedication".

Paddling pool

"I pay tribute to both the two leading designs. This was the judgment of Solomon.

"But there had to be just one winner. And now that we have one, we can move on to build a worthy memorial to Diana's life."

Miss Gustafson's design involves water pouring into the stone ring from the top of a hill at the Serpentine Bridge and running down in two directions.

Tessa Jowell and Rosa Monckton survey the site

Both end in a pool in a dished hollow. At night the shape, which can be planted with plants and trees, would be lit up.

The water will be shallow enough for children to paddle and play in. Ms Monckton described it as an "appropriate memorial" to Diana.

"We were privileged as a committee to be asked to pass judgment on such a large number of outstanding entries," she said.

Miss Gustafson said: "The ability to affect those with whom one comes into contact, while being affected by those around one - these were both attributes associated with Princess Diana.

"We have endeavoured to create a water feature that can be associated with these features."

The designers describe it as a place to find "serenity, a time and space to reflect".