Singapore thrives best when the entire region is stable and can attract investors, Prime Minister Lee Hsien Loong said as unrest continues to roil Hong Kong, often seen as the city-state's competitor for the role of Asia's premier financial center.

Speaking at the Forbes Global CEO Conference in Singapore on Wednesday, Lee said confidence in the region would mean that "investors can come and not think that 'I'm in a dangerous part of the world.'"

"We thrive best in Singapore when the region is stable, when other countries are prospering and we can do business with them," he told the audience at a dialogue with Steve Forbes, chairman and editor-in-chief of Forbes Media.

Those ties with other countries would include those in financial services with Hong Kong, tourism, or trade, Lee said.

"When Hong Kong is troubled, when there're demonstrations — or worse, riots — when the chief executive is booed out of the Legislative Council chamber, I think that's very sad for Hong Kong and very bad for the region," he said. He was referring to Wednesday's incident where Hong Kong Chief Executive Carrie Lam was heckled and interrupted by pro-democracy lawmakers twice while trying to make her annual policy address. She was forced to eventually deliver the speech by video.