For the second time this year, Malaysia has summoned China’s ambassador in Kuala Lumpur to protest against Chinese vessels breaching its exclusive economic zone in the South China Sea, where the Southeast Asian nation has rich oil and gas fields.

In a four-paragraph statement released late on Monday, the Malaysian Ministry of Foreign Affairs said that Chinese ambassador Ouyang Yujing was summoned “to convey Malaysia’s position and protest against the presence and activities of Chinese vessels, including a survey vessel, in Malaysia’s exclusive economic zone off the coasts of Sabah and Sarawak,” according to a report in the South China Post.

“The presence and activities of these vessels are inconsistent with Malaysia’s Exclusive Economic Zone Act 1984, as well as the 1982 United Nations Convention on the Law of the Sea (Unclos),” the statement said.

"Malaysia's consistent position and actions are based on international law, in defence of our sovereignty and sovereign rights in our waters," the foreign ministry said.

Last week, local media reported that a Chinese survey vessel was in Malaysian waters off the coast of Sabah, near a vessel commissioned by Malaysian state oil and gas company Petronas.

Last year also China had created problems when it sent a survey ship to obstruct the work of an oil exploration vessel contracted by Petronas within Malaysia's exclusive economic zone. China had at the time claimed that the vessel was conducting normal activities.

Malaysia's foreign ministry also said that all matters related to the South China Sea must be resolved peacefully and constructively.

"In determining Malaysia's position and course of action with regard to the South China Sea issue, which is complex and involves inter-State relations, Malaysia's national interests will remain of paramount importance," it said.

A belligerent China has been extending its claims in the South China Sea, which has rich oil and gas reserves and also lucrative fishing zones. China has been accused of bullying its smaller neighbours Malaysia, Brunei, the Philippines, Taiwan and Vietnam with conflicting claims over their territorial rights.

The Philippines and Vietnam have also accused China of harassing fishermen and hampering oil and gas exploration and production activities in the South China Sea.

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