SINGAPORE - Singapore's expanded port limits cover more or less the same area that Malaysia suddenly laid claim to on Oct 25.
The message is clear: "Back off" because these waters belong to Singapore, Transport Minister Khaw Boon Wan said on Thursday (Dec 6).
In contrast, through a series of charts, he showed that for years - since 1979 - Malaysia had claimed certain waters as its own and acknowledged that Singapore's waters lay beyond that.
But on Oct 25, in expanding the Johor port limits, Malaysia extended its claims to Singapore waters.
"They never made a claim on this area. These are our waters. But now on Oct 25 they decided to cross their own claim boundaries into Singapore waters and claim them as their waters."
He explained that where there are ports, it is common for limits to be marked to make clear where port activities such as bunkering take place.
Ships that call at the port also park within the demarcated zone.
Mr Khaw said: "So each country declares its own port limits; but obviously, you can only declare port limits within your own territories. You cannot be drawing port limits into my land, for example."
Countries are free to define and adjust their port limits, he said.
"You don't need to get approval from your neighbours because it is within your territory - and that is the bottom line. You can only define port limits with your own boundaries," he stressed.
Pointing to a chart showing Singapore's expanded port limits, Mr Khaw said during a media briefing: "We are expanding our port limits by this shaded area. But unlike the Malaysian adjustments, ours is within our own territorial waters.
"As I said just now, it is normal for countries to adjust port limits but you must do so within your own boundaries, and this is the case in our case. So the gazette is out and will take immediate effect."
Mr Khaw stressed: "We do it properly, in accordance with international law and certainly do not infringe on our neighbour's rights."
The last time Singapore amended its port limits was in 1997.
Asked what the Republic will do if neighbouring and other countries refuse to accept the expanded port limits, he said: "They have to comply. They must comply. This is our waters."
He stressed that Singapore will not hesitate to take "firm actions against intrusions and unauthorised activities in our waters to protect our territory and sovereignty".
Mr Khaw said that for more than 20 years, Singapore has exercised jurisdiction over its territorial waters, including its port limits.
"Our security vessels patrol this area. We do it all the time and whenever there are intrusions, we chase them away, we protest, we enforce. This is our area."
"They knew our activities - 'they' meaning Malaysia. They are familiar with our activities for more than 20 years. They never protested. They never made a claim on this area," he said.
"Now, out of the blue, Malaysia is claiming these territorial waters that belong to Singapore... Malaysia is seeking to alter unilaterally the longstanding status quo in the area," Mr Khaw added.
Noting that there have been 14 intrusions into Singapore territorial waters off Tuas since Nov 24, Mr Khaw said: "Our security agencies are enforcing this area, informing them, telling them to get out, move away and so on.
"Against all these aggressions, we have been extremely restrained, but I think we have a job to do... if need be we will take more firm actions."
Despite being pressed, though, Mr Khaw did not say what these actions could include.