Taiwan’s President has launched the island’s first domestically made submarine for testing at a port in Kaohsiung.

The submarine, if successful in its tests, will be a major breakthrough for Taiwan in shipbuilding and design.

President Tsai Ing-wen said at the launch ceremony: “In the past, a domestic-made submarine was considered impossible, but today a submarine designed and built by our countrymen is in front of you.”

She added: “Building submarine is the concrete realisation of our resolution to protect our country. Submarines are an important piece of equipment for the Taiwan navy to develop asymmetric combat power in terms of strategy and tactics.”

The US has been pushing Taiwan to develop asymmetric warfare strategies by investing in smaller and lighter weapons such as the reduced-size submarine.

The process was “torturous”, said Cheng Wen-lon, head of Taiwan’s CSBC Corp, which led the constructions of the submarine.

“Although we have worked quietly during the past several years, it doesn’t mean the process was very smooth,” he said at the ceremony held in CSBC’s shipyard.

After seven years of design and construction, the prototype will begin tests in the harbour before heading to the ocean.

The submarine is named Hai Kun after a fish in Chinese mythology called kun with legendary proportions.It will only be handed over to the military after passing both its harbour and ocean-faring tests.

Taiwan plans to build another submarine if successful, with both to be deployed by 2027, according to the semi-official Central News Agency.

Taiwan began building its own submarines after Beijing prevented it from purchasing such craft from abroad through use of economic and diplomatic threats.

In recent years, China has stepped up its military exercises aimed at the island, sending fighter jets and navy vessels to patrol and hold drills in the waters and skies near Taiwan.

In attendance at the ceremony were the heads of the US de facto embassy, Sandra Oudkirk, and the Japanese and South Korean trade delegations based in Taiwan.