BEIJING — The Taiwanese-controlled island of Kinmen located just off the Chinese coast has begun importing water from its neighbor via a pipeline despite heightened tensions between Beijing and Taipei.

Water from Jinjiang in China's Fujian province began flowing through the 16-kilometer (10-mile) -long pipeline Sunday under a 30-year contract.

The island, about three times the size of Manhattan, has long been short of water and hordes of tourists have put an extra strain on supplies.

The move shows how trade and other non-political ties have been relatively unaffected by the diplomatic freeze instituted two years ago by China, which claims Taiwan as a part of its territory to be annexed by force if necessary.

In recent months, China has increased Taiwan's diplomatic isolation and stepped up military threats by sending warplanes on patrols around the island and staging war games on its side of the Taiwan Strait.

It has also offered preferential terms for talented young people from the high-tech island to work in cities such as Shanghai and Beijing that offer much larger potential markets than those available in Taiwan.

China has taken an increasingly hard line since the election of Taiwanese President Tsai Ing-wen, who has refused to endorse Beijing's insistence that Taiwan is a part of China.

Kinmen was retained by Chiang Kai-shek's Nationalists as they fled the Communist takeover of the mainland in 1949. For years, it was bombarded by Communist artillery leaving it strewn with shells and its beaches covered in barbed wire.

With the end of open conflict, the island was opened to tourism in the 1990s and has grown increasingly popular with visitors from both China and Taiwan's main island. The $1.35 billion water project will provide Kinmen's 128,000 people with up to 55,000 tons of water per day.

The head of Kinmen's local government, Chen Fu-hai, has suggested the island could in future import electricity from China and even build a bridge to the mainland, drawing a rebuke from Taiwan's central government that such decisions weren't up to the local government alone.