Eleven countries have now ratified the Regional Cooperation Agreement on Combating Piracy and Armed Robbery against Ships in Asia (ReCAAP), a Japanese initiative launched in Tokyo in November 2004.
"The ReCAAP Agreement will enter into force on 4 September 2006," a foreign affairs ministry statement said.
Singapore serves as the depository of the agreement and will host the group's information sharing centre, a permanent body with full-time staff.
Cambodia, Japan, Laos, Singapore, Thailand, the Philippines, Myanmar, South Korea, Vietnam, India and Sri Lanka have all ratified the agreement, Singapore said, noting that 10 ratifications were needed for implementation of the pact.
Brunei has also signed and is in the process of ratification, Singapore said.
"The ReCAAP Agreement is the first regional government-to-government agreement to combat piracy and armed robbery against ships in Asia," it added.
Officials say vessels plying the Malacca Strait, which pass through Singaporean, Indonesian and Malaysian territorial waters, are vulnerable to pirates and seaborne "terrorism". The three countries have launched coordinated military air patrols over the waterway, one of the world's most vital sea lanes.