Malaysia has proposed that both countries cease sending ships into the disputed area starting midnight tonight, pending discussions on outstanding maritime boundary issues.

In a statement this evening, Foreign Minister Saifuddin Abdullah said this was communicated to the republic through the Singaporean High Commissioner in Kuala Lumpur.

"The action to desist would be undertaken without prejudice to either Malaysia or Singapore's position on maritime boundary claims over the area in question," he said.

He said Prime Minister Dr Mahathir Mohamad had forwarded a draft agenda for the meeting when he met with his Singaporean counterpart Lee Hsien Loong in Singapore last month.

"It is the hope of the Malaysian government that the meeting could be convened sometime in the middle of this month," said Saifuddin.

He said Malaysia had also communicated a protest against Singapore's decision to extend the country's port limits off Tuas.

Saifuddin said Singapore's Port Marine Circular No 9, dated Dec 6, was a unilateral port limit extension which encroached on the Johor Bahru port limits indicated under Gazette PU (B) 587 2018, dated Oct 25.

"This is a clear violation of Malaysia's sovereignty and international law.

"The government of Malaysia therefore called upon the government of Singapore to withdraw its Port Marine Circular No 9," he said.

Saifuddin's statement came just a few hours after Singapore Defence Minister Ng Eng Hen "strongly cautioned" Malaysian vessels against "encroaching" Singaporean waters.

Ng also posted an undated video clip of a Singaporean coast defence ship warning a Malaysian Maritime Department vessel.