Madrid - As Spanish artist Miquel Barcelo prepares for the unveiling of his most gigantic work so far at the United Nations headquarters in Geneva, he is at the height of his artistic glory.

Only a political squabble over the cost of the art work is casting a shadow over the ceremony, which will be attended by UN Secretary-General Ban Ki-moon, Spain's King Juan Carlos and Prime Minister Jose Luis Rodriguez Zapatero on Tuesday, November 18.

Barcelo, who is being compared with Pablo Picasso (1881-1973) and Joan Miro (1893-1983), worked for 13 months on redecorating a negotiating room which will now be known as the Chamber for Human Rights and the Alliance of Civilizations.

The Alliance of Civilizations project was launched by Zapatero and his Turkish counterpart Recep Tayyip Erdogan to improve dialogue between the West and the Muslim world in 2006.

The ceiling created by Barcelo, which has been compared with Michelangelo's work at the Sistine Chapel, turns the room into a cave dripping with thousands of multicoloured stalactites and swept over by a stormy sea.

"The cave is a metaphor for the agora, the first meeting place of humans, the big African tree under which to sit to talk, and the only possible future: dialogue, human rights," Barcelo explains.

"The sea is the past, the origin of the species, and the promise of a new future: emigration, travel," he adds.

The 51-year-old artist describes his new work as "reaching towards the infinite, bringing a multiplicity of points of view," like El Libro de Arena (The Book of Sand, 1975) by the late Argentine writer Jorge Luis Borges, whose grave Barcelo kept visiting during his stay in Geneva.

Few question the artistic value of the ceiling created by Barcelo, but its cost has sparked controversy.

The budget to renovate the room amounted to nearly 20 million euros (25 million dollars), 60 per cent of which was covered by Spanish sponsors.

The rest was given by the government, including 500,000 euros that were lifted from a development aid fund.

"Art has no price," Foreign Minister Miguel Angel Moratinos said, eliciting criticism from the conservative opposition which said the same money could have been used for vaccinating children or opening water holes in developing countries.

The money did not come from funds which would have been used for such projects, the government explained.

Talk about the money having been "stolen from the poor" did not correspond to reality, said Barcelo, whose used 35 tons of paint on the work measuring 1,400 square metres.

His team included 20 specialists ranging from a speleologist and a cook to architects and engineers. Special machinery was designed to create the artificial stalactites some of which weigh more than 50 kilogrammes.

Barcelo, who masters nearly all artistic techniques ranging from painting and sculpture to performance art, soared to fame early on, and is now regarded as one of the world's top contemporary artists.

Dividing his time between his native Majorca, Paris and Mali in West Africa, Barcelo has absorbed a wide range of influences ranging from European Baroque to African materials and themes.

"To think that art has made a lot of progress between (the cave paintings of) Altamira and (Paul) Cezanne is a vain and Western attempt," says the artist, who has described painting as "mud that I stir with a stick."

Fascinated by processes of transformation on land and in the sea, Barcelo sees his art as an "organized chaos" and as an "act of resistance."

Barcelo's biggest projects include modern terracotta murals for a Gothic chapel in the cathedral of Palma de Majorca, which were finished in 2007, but the award-winning artist has vowed not to become an "official dinosaur."

"I don't want to spend my life doing mega-projects or big pharaonic works," he says. (dpa)