The incident involving Malaysian vessel Polaris and a Greece-registered bulk carrier Piraeus happened at 2.30pm today, according to the Maritime and Port Authority of Singapore (MPA).

MPA said the Piraeus was on its way from Singapore to Tanjung Pelepas.

“MPA is deeply concerned that the presence of unauthorised vessels in Singapore Port Limits can cause confusion for the international shipping community and threaten navigational safety in our waters,” it said, adding that the incident was being investigated.

Singapore has accused Malaysian ships of encroaching into its waters off Tuas after Malaysia extended the Johor Bahru port limits in October last year.

In a tit-for-tat move, the city-state announced it was extending the Singapore Port Limits off Tuas, saying it was well within its territorial waters.

Last month, the Singapore government protested a visit by Johor Menteri Besar Osman Sapian to a Malaysian government vessel which it said had been “anchored illegally” in the waters off Tuas.

The republic later called off a Joint Ministerial Committee for Iskandar Malaysia (JMCIM) meeting, saying Osman’s action was “provocative”.