According to a report from the Mirror, The website of Taiwan’s presidential office has been hit by an overseas cyber attack ahead of a US diplomatic visit to the self-ruled island. The website was shortly brought back online, it emerged.

US House of Representatives Speaker Nancy Pelosi was expected to arrive in Taipei later on Tuesday, people briefed on the matter said, as frictions rose across the sensitive Taiwan Strait.

In a show of strength this morning, Chinese warplanes soared close to Taiwan’s maritime border, with the US Navy deploying four warships to the Taiwan Strait moments later.

In Fujian, the region closest to Taiwan, flights to the area have been canceled and military equipment, boats, and trucks can be seen being carried through Xiamen in China.

Arguments over the territory have lasted decades, ever since the Chinese Communist Party (CCP) took control of mainland China in 1949 following the civil war. It has continued to argue that Taiwan, where the opposing nationalist party fled to, is part of its territory.

Taiwan, which brands itself the Republic of China (ROC), has remained self-ruled, but the CCP views reunification with Taiwan as a key part of its Communist ideology and the country’s identity. This is also known as the “one China” policy.

The CCP has repeatedly insisted it was willing to decide the future of Taiwan with military strength and “will take resolute and vigorous countermeasures”, such is the strength of feeling among the party and the country’s leader Xi Jinping.

A spokesman for the Chinese Foreign Ministry, Zhao Lijian, said on Monday: “We once again sternly warn the US side that China stands at the ready and the Chinese People’s Liberation Army will never sit idly by.”