Cheung Kong Holdings and Hutchison Whampoa surged the most since at least 1998 in Hong Kong trading after billionaire Li Ka-shing announced a $24 billion ($30.7 billion) restructuring of his two main companies.

Cheung Kong gained 19 percent, the most since February 1998, to HK$148.30 as of 9:31 a.m. local time.

Hutchison, which is 50 percent controlled by Cheung Kong, advanced 16 percent, the biggest gain since October 1997, to HK$101. The benchmark Hang Seng Index rose 0.8 percent.

The 86-year-old tycoon proposed late on Jan. 9 to reshuffle the assets of his companies into two new entities with specific focuses: one on property mainly in Hong Kong and China, and the other on global assets from utilities and ports to retail stores across more than 50 countries.

The streamlined structure will allow shareholders to more easily choose which businesses they want to invest in.

“The reorganization should unlock the true value of its property business, which trades at a deep discount,” Mizuho Securities Co. analysts Alan Jin and Doris Hu said in a note today.

The deal will also “reduce unnecessary layering within the two groups” and increase transparency, they said.

Cheung Kong Property Holdings, the new company which will fold in all of the real estate assets held by Cheung Kong and Hutchison, could become Hong Kong’s biggest listed property company.

The combined revenue from Li’s property portfolio was HK$54.4 billion ($8.9 billion) in 2013, compared with HK$40.1 billion for Sun Hung Kai Properties in the same period, according to UBS AG.

All of Li’s non-property assets, including stakes in Cheung Kong Infrastructure Holdings and the recently acquired aircraft leasing business, will go into the other new company, CK Hutchison Holdings.

The new structure would allow Li more flexibility to invest in new businesses outside of Cheung Kong’s and Hutchison’s traditional areas, Canning Fok, his long-time deputy said at a press briefing late on Jan. 9.

Li and his family trusts currently own 43 percent of Cheung Kong, which controls Hutchison. Following the restructuring, they will have a 30 percent stake in each of the new companies, increasing their free float.