Hong Kong billionaire Li Ka-shing's flagship CK Hutchison Holdings posted a net profit of over US$13 billion in the first half of the year, in its first earnings report since a sweeping reshuffle of Li's business empire.

The firm, which controls assets in telecoms, utilities, ports and other industries in over 50 countries, reported a net profit of HK$101.86 billion ($13.14 billion) for the six-month period, while revenue stood at HK$117.25 billion.

The results were not comparable to the same period last year with the octogenarian's Cheung Kong and Hutchison Whampoa merging assets in June.

Li sounded a note of caution over the results due to "weak" global growth.

"External conditions in the first half remained challenging with weak global growth, sustained low commodity prices, uncertainty as to monetary policy directions and increased currency volatility," he said in a statement filed to the city's bourse.

CK Hutchison saw its shares up 3.8 percent at the close in Hong Kong at HK$102.3 per share before the results were announced.

The news came amid concerns of a slow down in China, with stocks in the world's second-largest economy pursuing their worst rout in nearly two decades.

Li's Cheung Kong Property Holdings, which was spun off from his conglomerate in June, meanwhile said first half net profit was up 22 percent at HK$6.89 billion.

"Looking ahead, the overall market conditions in Hong Kong and the mainland will remain stable in the second half year barring no major unforeseen material adverse developments," Li said in the company's statement.

Under the reshuffle of Li's empire, Cheung Kong changed its name to CK Hutchison Holdings, while all property-related business came under the control of CK Property, a newly listed company.

Hutchison Whampoa, trading on the city's bourse since 1978, was delisted.

Li said the overhaul was to secure stability in future, while it was also seen as paving the way for the 86-year-old to hand over the reins to his eldest son Victor, 51, after he retires.

The 87-year-old lost the title of the richest man in Asia in December after holding it since 2012 to Chinese entrepreneur Jack Ma, founder of recently listed e-commerce giant Alibaba.

Li, currently worth $30.4 billion according to the Bloomberg Billionaires index, first started his own business in 1950 manufacturing plastic flowers.