The Philippines, Malaysia, Taiwan and Vietnam have rejected as baseless a map released by China that denotes its claims to sovereignty including in the South China Sea which Beijing said on Thursday should be viewed rationally and objectively.

China released the map on Monday of its famous U-shaped line covering about 90% of the South China Sea, a source of many of the disputes in one of the world’s most contested waterways, where more than $3 trillion of trade passes each year.

The Philippines called on China on Thursday “to act responsibly and abide by its obligations” under international law and a 2016 arbitral ruling that declared the line had no legal grounds.

Malaysia said it had filed a diplomatic protest over the map.

China says the line is based on its historic maps. It was not immediately clear whether the latest map denotes any new claim to the territory.

China’s U-shaped line loops as far as 1,500 km (932 miles) south of its Hainan island and cuts into the exclusive economic zones (EEZs) of Vietnam, the Philippines, Malaysia, Brunei and Indonesia.

“This latest attempt to legitimise China’s purported sovereignty and jurisdiction over Philippine features and maritime zones has no basis under international law,” the Philippine Foreign Ministry said.

Its Malaysian counterpart in a statement said the new map holds no binding authority over Malaysia, which “also views the South China Sea as a complex and sensitive matter”.

The map was different to a narrower version submitted by China to the United Nations in 2009 of the South China Sea that included its so-called “nine-dash line”.

The latest map was of a broader geographical area and had a line with 10 dashes that included democratically governed Taiwan, similar to a 1948 map of China. China also published a map with a 10th dash in 2013.

Asked about the latest map, Taiwan Foreign Ministry spokesperson Jeff Liu said Taiwan was “absolutely not a part of the People’s Republic of China”.

“No matter how the Chinese government twists its position on Taiwan’s sovereignty, it cannot change the objective fact of our country’s existence,” he told a press briefing.

China is currently having a “national map awareness publicity week”, state broadcaster China Central Television reported on Tuesday.

Asked why China had released the latest map with 10 dashes compared to one with nine dashes, Chinese Foreign Ministry spokesperson Wang Wenbin said Beijing had been unambiguous about its territory.

“China’s position on the South China Sea issue has always been clear. The competent authorities of China regularly update and release various types of standard maps every year,” he told a regular briefing.

“We hope that relevant parties can view this in an objective and rational manner.” Late on Thursday, Vietnam’s foreign ministry said China’s claims based on the map have no value and violate Vietnamese and international laws.

Vietnam “resolutely rejects any claims in the East Sea by China that are based on the dashed line,” Ministry of Foreign Affairs spokesperson Pham Thu Hang said in a statement, referring to the South China Sea.

Separately, Hang said Vietnamese authorities are seeking to clarify an allegation by Vietnamese fishermen that a Chinese vessel attacked their fishing boat with a water canon earlier this week in the South China Sea, injuring two of them.

“Vietnam opposes the use of force against Vietnamese fishing boats operating normally at sea,” she said in a statement sent to Reuters.

India said on Tuesday said it had lodged a strong protest with China over a new map that lays claim to India’s territory, the latest irritant in testy ties between the Asian giants.