The number of billionaires on China's mainland is expected to exceed the combined number of billionaires in the United Kingdom, Russia, France and Switzerland by 2023, [Hong Kong company registration]a report said Tuesday.

The growth in billionaire numbers is fueled by positive outlook for wealth creation in the country which is set to add an extra US$1 trillion to global GDP every year from 2013 to 2023, according to an annual wealth report by Knight Frank.

The number of ultra high-net wealth individuals (UHNWIs), with US$30 million or more in net assets excluding their main residence, meanwhile, is forecast to jump 80 percent to exceed 14,200 in China by 2023, said the world's leading independent property consultancy,[Set Up Company Hong Kong] which released the eighth edition of the annual report this year.

In Asia, the number of UHNWIs is set to exceed 58,500 by 2023, overtaking the total number in North America.

Based on the growth forecast in terms of UHNWI populations over the next 10 years, 19 of the top-20 cities are from Asia where Ho Chi Minh City in Vietnam emerged top. And 15 of the cities are from China.