Chinese President Xi Jinping has said the complete reunification of Taiwan with the motherland must be realised, declaring that the tide of history cannot be stopped, in a speech in Beijing that restated China's position on the island in the firmest terms. The comments came as tensions around Taiwan continue to rise, with the G7 warning that China's actions in the waters east of the island threaten regional stability.

Xi was speaking on Thursday at a gathering in Beijing's Great Hall of the People to commemorate the 160th anniversary of the birth of Sun Yat-sen, the revolutionary hero who helped lead the 1911 revolt that ended centuries of rule by emperors. Resolving the Taiwan question is an "unwavering historical mission" of China's Communist Party, Xi said, and the complete reunification of the motherland "must be realised, and it will certainly be realised".

The Chinese leader said China adheres to peaceful reunification and the policy of "one country, two systems", and is willing to talk to Taiwan on the basis of upholding the one-China principle. He made no mention of the use of force, but his emphasis on reunification as a historical inevitability will be read in Taipei and in Washington as a signal that Beijing's patience is not unlimited.

China views democratically governed Taiwan as its own territory, despite Taipei's strong rejection of that claim, and has repeatedly offered a "one country, two systems" model of autonomy that is not supported by any major Taiwanese political party. The island's government has said repeatedly that only Taiwan's people can decide its future, and that the island has never been ruled by the People's Republic of China.

Xi's speech came a day after the foreign ministers of the G7 said China's increasingly assertive actions in the waters east of Taiwan threatened regional stability and freedom of navigation. In a joint declaration published late on Wednesday after a meeting in Paris, the ministers said China's activities "threaten regional stability, freedom of navigation and the safety of international shipping".

China has stepped up its activity off Taiwan's east coast since June, with regular coast guard patrols and what Taiwan's defence minister, Wellington Koo, has described as "area denial" drills in the Western Pacific involving one of China's aircraft carriers and other naval formations. Taiwan's military operates around the island on a daily basis, and the two sides have been locked in a pattern of patrols and counter-patrols for years.

The timing of Xi's speech is also significant. It comes as the United States and China prepare for a round of high-level diplomacy, with President Donald Trump due to visit China for the APEC summit and Chinese President Xi Jinping expected to visit Florida for the G20 summit. US Secretary of State Marco Rubio spoke with Chinese Foreign Minister Wang Yi on Wednesday, and the two sides agreed on the importance of leader-level conversations, including a possible trilateral meeting with Russia on peace and denuclearisation.

The Taiwan question has been at the centre of US-China tensions for decades, and Xi's speech will be watched closely in Washington. The United States is bound by law to provide Taiwan with the means to defend itself, and has repeatedly warned Beijing against any attempt to change the status quo by force. At the same time, Washington has said it does not support Taiwan independence, a position that leaves the island in a delicate balance between the two great powers.

For Taiwan, the speech is a reminder of the pressure it lives under. The island's government welcomed the G7 statement, and has said it will continue to defend its democracy and its way of life. But the gap between Beijing's insistence that reunification is inevitable and Taipei's insistence that it will decide its own future has never been wider, and the risk of miscalculation grows with every patrol and every speech.

Xi's words, delivered in the Great Hall of the People on an anniversary that celebrates the man who overthrew the empire, were aimed as much at history as at the present. Sun Yat-sen is revered on both sides of the Taiwan Strait, and Xi's invocation of him was a deliberate choice, framing reunification not as a political demand but as the completion of a national mission that began more than a century ago. Whether that mission can be completed peacefully, as Xi insists it can, will be one of the defining questions of the years ahead.