China's central authorities issued a plan on Monday for further development of a cooperation zone for Shenzhen and the Hong Kong Special Administrative Region.

The plan will "give full play to Hong Kong's long-held advantages in high-end professional services", lifting cooperation between the cities to a higher level, an official said.

According to the plan, the reform and opening-up of the Qianhai Shenzhen-Hong Kong Modern Service Industry Cooperation Zone will be comprehensively deepened. It proposes increasing the area of the Qianhai cooperation zone from 14.92 square kilometers to 120.56 square km.

The plan is underpinned by institutional innovation and will be implemented by pilot programmers under the framework of "one country, two systems" to promote the convergence of rules and mechanisms of the Hong Kong and Macao special administrative regions for coordinated development.

It plans to create a test platform for deepening reform and innovation in the Guangdong-Hong Kong-Macao Greater Bay Area and to build a high-level gateway for opening-up.

By 2035, Qianhai will boast a world-class business environment, and will become an engine for high-quality development with strong capability in global resource allocation, encouraging innovation and leading coordinated development, according to the plan.

"The plan is like timely rain. It not only enriches the connotation of regional cooperation and platform construction in the 14th Five-Year Plan (2021-25), but also focuses on utilizing Hong Kong's traditional advantages of a high-end professional services industry," a spokesperson of the Liaison Office of the Central People's Government in the Hong Kong SAR said on Monday.

"It will definitely provide great opportunities for Hong Kong professionals and enterprises."

Hong Kong Chief Executive Carrie Lam Cheng Yuet-ngor said the plan will foster Hong Kong-Shenzhen cooperation at a higher level.

"Not only does the plan give full play to Hong Kong's long-held advantages in high-end professional services, and elevate the function of the Qianhai Shenzhen-Hong Kong Modern Service Industry Cooperation Zone, but it also promotes long-term development of Hong Kong professional services," she said on Monday.