Referring to Aukus, a trilateral security pact agreed last month between Australia, the United States and the UK, Saifuddin said the two Southeast Asian nations were concerned about the ramifications.

“We agree on the latest issue in the region regarding a country near our territory that is purchasing new nuclear-powered submarines,” Saifuddin told a joint news conference after a meeting with counterpart Retno Marsudi.

“Even though that country doesn’t have the capacity for nuclear weapons, we are worried and concerned.”

Indonesia had said last month that it was concerned Aukus could lead to a regional arms race.

The deal comes amid increasing tensions in the East and South China Seas, conduits for trillions of dollars of shipments amounting to about a third of global trade.

The Philippines, a US defence treaty ally, has backed Aukus, saying it offers a necessary counterbalance to an increasingly assertive China.

Malaysia previously said it would seek the views of China and Asean on the issue.

The Indonesian and Malaysian ministers also expressed disappointment with the Myanmar junta’s lack of progress in implementing an agreed peace plan with Asean.

Asean had on Friday decided to exclude junta chief Min Aung Hlaing, who led a Feb 1 coup, from an upcoming regional meeting, in an unprecedented snub by the bloc.

Asean will continue to offer humanitarian assistance to Myanmar, said Marsudi.

The foreign ministers also said they were in discussion about starting a travel corridor between Indonesia and Malaysia, and had agreed to finalise maritime sea borders in southern Malacca and the Sulawesi Sea.