The foreign ministry also said a police report will be filed for a thorough investigation by the relevant authorities.

“The ministry views the leak of this document, which constitutes an official communication channel between the two countries, with grave concern,” it said in a statement today.

Last week, the portal reported that Beijing had demanded that Malaysia immediately cease activities in an oil-rich area off Sarawak waters.

The document dated Feb 18, which the portal published, accused Malaysia of encroaching into territories covered by the controversial nine-dash line, a map representing Beijing’s claims in the South China Sea.

Malaysia had previously said that it did not recognise the 2023 standard map, which showed portions of Malaysian waters near Sabah and Sarawak as belonging to China.

Beijing has delineated the nine-dash line to assert its historic claim over 90% of the contested waters.

In the statement, the foreign ministry reaffirmed that both Malaysia and China are committed to resolving South China Sea issues through peaceful consultation and dialogue, without resorting to disputes or violence.

It reiterated that Malaysia would continue to defend its sovereignty and maritime interests based on the 1979 Malaysia Map, in line with international law and United Nations Convention on the Law of the Sea (UNCLOS) 1982.

However, as part of efforts to keep the South China Sea as a region of peace and trade, the ministry also said Malaysia would continue to prioritise diplomatic engagement with other countries, including China.

“This is in line with the provisions of the Declaration on the Conduct of Parties in the South China Sea, which emphasises the resolution of disputes by peaceful means and the avoidance of threats or use of force.”

It added that Malaysia remains committed to the negotiations between Asean member states and China to finalise a substantive and effective Code of Conduct in the South China Sea by the provisions of UNCLOS 1982.