Rallies are planned for Saturday in more than 950 cities across 82 countries in Europe, North America, Latin America, Asia and Africa in a show of power by a movement born on May 15 when a rally in Madrid's central square of Puerta del Sol sparked a protest that spread nationwide, then to other countries.

Around 500 people gathered in the heart of Hong Kong's financial district to express their anger at the inequities and excesses of free-market capitalism, while demonstrators in Tokyo also voiced fury at the Fukushima nuclear accident.

Wong Weng-chi, a demonstrator from a group calling themselves "Left 21", said the "Occupy Central" rally in Hong Kong was more than just an act of solidarity with the Wall Street protest, which began in September.

"Hong Kong is a key financial hub in Asia, it is a base that serves many multinational financial institutions. It is a base that serves many capitalists and the upper class to monopolise the wealth," he told AFP.

Hong Kong, a city of seven million people, is known for its super-rich tycoons, low taxes and teeming shopping districts.

But it is also a case study in economic inequality, with thousands of low-income residents forced to live in "cage" accommodation because of the skyrocketing cost of housing fuelled by wealthy property speculators.

Around 600 demonstrators in Sydney set up camp outside Australia's central bank. Corporate greed, the political influence of big firms, climate change and the plight of refugees and Aboriginal Australians were repeatedly raised as issues.

In Tokyo, around 100 protesters marched through the streets, shouting "Occupy Tokyo!". They added anti-nuclear slogans as they passed the offices of Tokyo Electic Power Co, the operator of the stricken Fukushima plant.

Tomoko Horaguchi, a 22-year-old student at Hosei University, said she was moved by the protesters on Wall Street.

"I feel the same anger," Horaguchi said. "In particular I am angry at nuclear power plants. Only one percent of people want to run them still."

The Fukushima nuclear accident, the world's worst since Chernobyl, was sparked after the March 11 earthquake and tsunami crippled the plant's cooling systems and led to reactor meltdowns and radiation leaks.

In Seoul, a group of some 70 activists braved driving rain to rally outside the headquarters of South Korea's financial watchdog, the Financial Supervisory Service, waving banners and chanting slogans.

"Occupy Yeoido," they shouted in reference to the city's main financial district. "We're the 99 percent."

About a dozen riot police stood side by side outside the entrance to the building to keep the protesters away.