(Bloomberg) -- Malaysia and Singapore have issued more comments on a territorial dispute between the two nations. Singapore claims Malaysian government ships vessels are intruding into its waters.

The statements signal a potential escalation in the war of words between the two Southeast Asian countries, a level of bickering not seen in years. The duo, which were once part of the same country, had a fractious relationship during Malaysian Prime Minister Mahathir Mohamad’s first stint in power from 1981 to 2003.

Mahathir Mohamad, speaking at a press conference near Kuala Lumpur on Saturday said:

“The important thing is that Singapore agreed to a negotiation. We cannot give a final answer” until the negotiations are resolved.

On why Malaysia decided to extend its Johor Bahru port, which Singapore alleges is an encroachment on Singapore waters, he said:

“Lots of people announce their borders off and on and that causes a lot of dispute. We will settle the dispute based on legal provision and our rights.”

Singapore Minister for Trade and Industry Chan Chun Sing, speaking to reporters Saturday, according to the Straits Times newspaper, said:

Malaysia must get its government vessels to leave Singapore territorial waters at once and return to the pre-Oct. 25 status quo, Chan said.

Singapore welcomes talks and hopes for a “swift and amicable resolution” of the matter. The Singapore government is also prepared for the dispute to be resolved “by recourse to an appropriate international third-party dispute settlement procedure.” But it was important, he said, to “calm down the ground situation first.”

“We know that some ships are armed. So the risk of escalation cannot be underestimated. Accidents can happen.”

Read More: Why Singapore and Malaysia Are Locking Horns Again: QuickTake

To contact the reporters on this story: Wes Goodman in Singapore at wgoodman@bloomberg.net;Anuradha Raghu in Kuala Lumpur at araghu3@bloomberg.net

To contact the editors responsible for this story: Stanley James at sjames8@bloomberg.net, John McCluskey, Kana Nishizawa

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