The U.N.'s Palace of Nations is falling apart.

The Palais des Nations is the U.N.'s European headquarters, flanked by the Swiss Alps to the west and Lake Geneva to the east. Peacocks roam freely on the grounds of the pristine, 111-acre Ariana Park that surrounds it.

But on the inside, the onetime home to the League of Nations is plagued by 70-year-old wiring, fire hazards and miles of rusty pipes that have flooded the archives repeatedly. Asbestos lines some of the walls, and the roof is in danger of caving in. The palace is in need of a major facelift.

The tab: one billion dollars, says Director General Sergei Ordzhonikidze, who heads the U.N. Office at Geneva.

But critics say it's not worth a cool billion to preserve a diplomatic palace. They say new offices could be built for less, and the money could be spent to heal the sick and feed the hungry.

For $1 billion, a firm could build 407,244 square meters of office space in Geneva. That's one and a half times the size of the Empire State Building, and five times the size of the main building at the Palais des Nations.

Based on 3,000 Swiss francs per square meter, a figure provided by Mario Botta Architetto, an architecture firm based in Switzerland, 407,244 square meters is two-and-a-half times the size of the entire Palais complex, which includes new wings and an underground garage.

A comparable building in the U.S. would cost about $228 per square foot, according to Kermit Baker, chief economist for the American Institute of Architects. That translates into almost precisely the same amount of brand new office space — 407,469 square meters.

Baker said those costs would cover construction only, and wouldn't pay for any expenses for design, buying land, brokering the deal or any changes in plans along the way, which are significant.

But the difference is massive; keeping the Palais des Nations could cost more than double what it would take to build a new home from scratch.

"We are extremely conscious that our mandate is not to do renovations for the pleasure of renovations. This is not our purpose," said Marie Heuze, chief spokeswoman for the U.N. Office at Geneva.

Heuze said the buildings are a storehouse of history and stand as a symbol of international cooperation. Every year about 100,000 visitors come to the palace, where tours are led in 15 languages.

Heuze told FOXNews.com that the director general's figure isn't on the U.N. budget yet and is an estimate that would have to be evaluated by a team of architects. Any major work on the Palais would likely come after the $1.9 billion renovation of the U.N.'s New York headquarters is complete.

Yet relief groups expressed bewilderment at the scope of the suggested renovations. Non-governmental organizations said $1 billion represents more than twice the amount the U.S. government spends worldwide on child survival and maternal health aid.

That $1 billion, relief groups said, is also larger than the entire humanitarian action appeal for all countries served by UNICEF, the United Nations Children's Fund, which requested $850 million to address 39 humanitarian emergencies around the world in 2008.

$1 billion could also go a long way to feed the hungry. Oxfam America reports on its Web site that "$1,000 brings potable water to 22 families in the Rift Valley of Ethiopia," and that "$20 buys enough maize to feed a family of four" there for six months — enough food and water to feed millions and flood the valley.

Critics are up in arms about the U.N.'s possible billion-dollar plan.

"This is entirely consistent with their spending habits worldwide for years," said Claudia Rosett, a U.N. watcher at the Foundation for Defense of Democracies. "For them to spend this kind of money, especially at a time when so many people are in economic distress, is outrageous."

The U.N. said its plans may slow as a result of the world's economic downturn. "With the financial crisis, of course, it seems very frivolous to talk about the renovation of a building which is old and dates from before the Second World War," said Heuze.

Renovations of massive scale may not be considered until 2009-2010, and they would have to be approved by a vote in the General Assembly — meaning all member nations would have a say in the expenditures.

But changes have already started in Geneva. A massive meeting hall was unveiled last week by Secretary General Ban Ki-moon, adorned with a $23 million art ceiling by the Spanish artist Miquel Barcelo. A number of other meeting rooms have been redone in recent years at a cost of hundreds of thousands of dollars, generally donated by foreign governments.

"There is constantly some renovation work done in the Palais des Nations, but much more needs to be done," Heuze said.

• Click here to see photos the $23 million ceiling art.

Director General Ordzhonikidze renovated his office this year, though the U.N. would not say how much the changes cost and did not specify whether a member state paid for the work. A spokeswoman said that his office was often overheated by the sun, and he had an air conditioner installed to cool it.

Sitting behind his desk in the Palais in June, Ordzhonikidze addressed the level of decay at the palace in an interview with Reuters.

"This door leads to a balcony. If you go out on the balcony, you see that everything is rusted. It's not nice," he said.