China was responding to a report that the British Royal Navy sent the HMS Albion - a 22,000-tonne amphibious warship carrying a contingent of Royal Marines - on a freedom of navigation operation last month, passing near the disputed Paracel Islands.
The Royal Navy said the warship sailed past the islands en route to Ho Chi Minh City, Vietnam, to demonstrate its "freedom of navigation" rights and challenge Beijing's "excessive claims" in the region.
A Chinese frigate and two helicopters were dispatched to intercept HMS Albion as it sailed past the Parcels, whose islands are also claimed by United States allies Taiwan and Vietnam. "In accordance with the Law of China on the Territorial Sea and the Contiguous Zone, the Chinese government promulgated the baseline of the territorial sea of the Xisha Islands in May, 1996".
Beijing claims most of the resource-rich sea, through which US$5 trillion in shipping trade passes annually, with competing claims from Brunei, Malaysia, the Philippines, Taiwan and Vietnam.
China's the Foreign Ministry alleges Albion entered Chinese territorial waters around the Paracel Islands without permission.
"Britain's actions were wrong", said Chinese Foreign Ministry spokeswoman Hua Chunying.
China's foreign ministry said on Thursday that it had made solemn representations to the United Kingdom about the incident, vowing to go to any length to defend its sovereignty. "China will continue to take all necessary measures to defend its sovereignty and security".
Beijing on Thursday strongly criticised London's actions, calling the recent incident a provocation.More news: Mother mistakes dynamite for candle during power outage
Britain has been courting China for a post-Brexit free trade deal, and both countries like to describe how they have a "golden era" in ties.
The U.S. and other nations have increased their air and sea presence in the region to underscore what the Pentagon says are global freedom of navigation rights.
The Navy's Ronald Reagan Strike Group joined with a defense flotilla of Japan to conduct joint military exercises in the South China Sea, the latest show of freedom of navigation resolve in the contested waters.
Last month, the UK Defence Secretary Gavin Williamson gave a speech in Washington in which he said China needed to recognise and abide by global norms.
But the Royal Navy's mission in the South China Sea, one of China's most sensitive issues, risks undermining the relationship. "It might also nudge other US allies to make similar moves".
Over the past year, China has significantly increased its military presence in the region by deploying jamming technology, anti-ship cruise missiles, and surface-to-air missiles at its outposts in the South China Sea.
"The Chinese Navy verified and identified the warship according to law and warned it to leave".
An worldwide arbitration panel in the Hague ruled in 2016 that China's claims have no legal standing.