HONG KONG (Reuters) – China’s Ministry of Defence on Tuesday warned the Netherlands to restrain actions of its naval and air forces after the Netherlands’ defence ministry said that Chinese fighter jets approached a Dutch ship ‘unsafely’ in the East China Sea.

“We strongly deplore the heinous nature of the Dutch side’s words and deeds, and have lodged solemn representations with them,” the Chinese defence ministry said.

Chinese air force jets circled a Dutch frigate and approached a Dutch helicopter in the East China Sea in a way that “caused a potentially unsafe situation,” the Netherlands’ Defense Ministry said on Saturday.

In a statement, the ministry said the HNLMS Tromp was patrolling on Friday in support of U.N. sanctions against North Korea when it was circled several times by two Chinese fighter jets.

Later, the ship’s NH90 helicopter was approached by two Chinese fighter jets and a helicopter.

Zhang Xiaogang, a spokesman for China’s Defense Ministry said the Dutch side was “falsely claiming to be carrying out a UN mission and flexed its force in the sea and air space under the jurisdiction of another country, creating tension and undermining the friendly relations between the two countries.”

Zhang said that China wanted to warn the Dutch side that “infringement and provocation will be resolutely countered by the Chinese side.”

Both China and Japan claim a group of islets in The East China Sea, which has long been a sticking point in bilateral ties.

(Reporting by Farah Master and the Beijing newsroom; Editing by Shri Navaratnam and Michael Perry)