Britain’s defence ministry is trying to justify its existence and grab attention with a planned warship mission through the disputed South China Sea, a Chinese newspaper has said.

The HMS Sutherland will sail through the South China Sea to assert freedom-of-navigation rights, according to remarks made by the British defence secretary, Gavin Williamson, while visiting Australia.

British officials first flagged the voyage six months ago and the journey is likely to stoke tensions with China, which claim control of most of the area and has built military facilities on land features in the sea.

Brunei, Malaysia, the Philippines, Taiwan and Vietnam also have claims to the energy-rich sea through which billions of dollars in trade pass each year.

Widely read state-run tabloid the Global Times said Williamson needed to state clearly the purpose of the mission.

“If not provocation, the Royal Navy should behave modestly when passing through the South China Sea,” it said in editorials published in its English and Chinese-language editions.

“By acting tough against China, Britain’s Ministry of Defence is trying to validate its existence and grab attention.”

China has repeatedly accused countries outside the region – generally a reference to the United States and Japan – of trying to provoke trouble in the South China Sea at a time when China and its neighbours are trying to resolve the matter through diplomacy.

Speaking of Britain’s plan, China’s foreign ministry said it hoped “relevant sides don’t try to create trouble out of nothing“.

Britain will be leaving the European Union next year and has looked to China as one of the countries where it wants to sign a free trade deal. The prime minister, Theresa May, wrapped up a largely successful trip to China earlier this month.