(Bloomberg News) Billionaire Carlos Slim, the world's richest man, gives a sneak peek tonight at his new Soumaya Museum in Mexico City, representing one of his biggest gifts to the art and museum worlds.

The gleaming, aluminum-plated structure, which cost an estimated $34 million, will be free to visitors. The Carlos Slim Foundation will underwrite all of the museum's expenses, including maintenance and the cost of mounting exhibitions.

"There will be no specific budget of a certain amount," said Slim, worth an estimated $69.5 billion, in a recent interview at Bloomberg News's New York headquarters. "There will be no limits. We will decide what needs to be done at the museum and just do it."

The museum was designed by Slim's son-in-law, architect Fernando Romero, 39, who apprenticed under Pritzker Prize winner and urbanist Rem Koolhaas. The 150-foot-tall building is named after Soumaya Domit, Slim's wife, who died of kidney failure in 1999.

The Soumaya, which opens to the public on March 28, will display some works from Slim's 66,000-piece collection. It includes works by Mexican masters such as Diego Rivera, Spanish masters Pablo Picasso and Salvador Dali, 15th-century European masters and the second-largest private collection of Auguste Rodin sculptures outside of France.

Slim's Pickings

Slim said he had a hand in choosing the works from his collection that would be displayed on the museum's six exhibition floors. He also created the museum's logo, which is Soumaya, in his own handwriting.

The museum is part of a 12-acre urban development that will include the corporate headquarters for Slim's business conglomerate, Grupo Carso, and Telcel, the Mexican mobile-phone company he controls. It will share space with a small shopping mall, two upscale apartment towers and an underground theater.

"This museum is for the Mexicans who cannot travel outside Mexico, so that they have a place to see this art in their country," Slim said.

The museum significantly increases Slim's profile as a Mexican cultural philanthropist. The son of a Lebanese immigrant who ran a dry-goods store in Mexico, Slim once managed his businesses from a windowless bunker-like office.

Land Lines

He built his fortune by buying businesses such as a bottling company and a cigarette maker. In 1990, he bought Telefonos de Mexico (Telmex) through a privatization sale. His holdings in America Movil SAB, Latin America's largest mobile-phone carrier, were valued at about $49 billion at the end of 2010. More than two-thirds of his wealth comes from his stakes in America Movil and Telmex, the nation's biggest land-line phone company.

Slim said the arts won't become a key focus of his future philanthropy. He'll continue to fund and address health, education, sports and public welfare issues through his telecommunications company's Telmex Foundation and the Slim Foundation.

"In the world of culture, we will operate a museum and we will find other works and we will lend the collection to other museums," he said. "Health and education is where our efforts are focused and we want to support human capital. The most important way to take people out of poverty is through employment."

Slim said he won't join the Giving Pledge started by billionaires Warren Buffett and Bill Gates to encourage the world's wealthiest people to promise to give away half of their wealth to charity. More than 50 billionaires have joined the pledge including David Rockefeller, Eli Broad, Sanford Weill and Ted Turner.

"When you are an investor maybe you can sell your investments, but it's important for me to develop these companies," he said. "We don't think it's necessary to give away half. Why half? Why not 80% or 70% or 60%?"