Chinese President Xi Jinping on Sunday sent a congratulatory letter on the opening of a cross-sea link between the cities of Shenzhen and Zhongshan in south China's Guangdong Province.

Xi, also general secretary of the Communist Party of China Central Committee and chairman of the Central Military Commission, said the Shenzhen-Zhongshan Link is another large-scale transportation project in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) following the Hong Kong-Zhuhai-Macao Bridge.

The project has managed to overcome multiple world-class technical challenges and set multiple world records, he said.

All participants, through their hard work and unwavering determination, have successfully completed the project with high quality, Xi said.

"This fully illustrates that Chinese modernization can only be achieved through solid work, as all great causes are accomplished through concrete actions," he said.

Next, efforts should be made to manage and make the most of the link to ensure its safe, smooth, easy and smart operation, Xi said.

The pioneering role of transportation should be given full play to promote the integrated development of both sides of the Pearl River Estuary, improve the GBA's "hard interconnectivity" of infrastructure and "soft interconnectivity" of rules and mechanisms, and advance the integration of the GBA market, he said.

That is to help and guarantee building the GBA into a strategic pivot point of China's new development pattern, a demonstration zone for high-quality development, and a leading area for Chinese modernization, Xi added.

After seven years of construction, the Shenzhen-Zhongshan Link, a mega cross-sea passage that features two bridges, two artificial islands, and an underwater tunnel, opened to traffic at 3 p.m. on Sunday.

Spanning 24 kilometers, the link drastically reduces travel time between the city of Zhongshan and the technology hub of Shenzhen, situated on opposite sides of the Pearl River Estuary, cutting the duration of the trip from two hours to around 30 minutes.

The new transport route boasts eight lanes designed for speeds of up to 100 km per hour.

It is a core transportation hub project in the GBA, which encompasses Hong Kong and Macao special administrative regions, and nine cities in Guangdong Province, covering 56,000 square kilometers. The area achieved a total economic output of over 14 trillion yuan (around $1.96 trillion) in 2023.

China aims to develop the area into a world-class city cluster, a global technology and innovation center, and a livable business-friendly location.

(With input from Xinhua)