Roslan Rahman | AFP | Getty Images

A general view shows the Marina Bay Sands hotel and resort in Singapore on March 19, 2016.

A resort hosting casinos in Japan could cost up to $10 billion to construct, Las Vegas Sands' chief said on Tuesday, as the casino operator looks to win operating rights in what is widely expected to become the world's second-biggest casino market.

"It would be at least what we paid in Singapore, $6 billion including the land, but it could be as much as $10 billion," said Chairman and Chief Executive Officer Sheldon Adelson at an investor conference in Tokyo, referring to Sands' Marina Bay Sands property in Singapore.

Adelson added that the opportunity was bigger than the casino run by the company in Singapore.

"It's the holy grail. It's the ultimate of business opportunities. Singapore was a warm up to this."

Japan legalized casinos late last year and is now drafting rules, due by December, on how to regulate the industry and pick operators and locations of so-called "integrated resorts" - large-scale complexes combining casinos, hotels and shopping.

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CNBC's Akiko Fujita contributed to this report.