Foreign ministers and defense officials of the three neighboring countries agreed to work together to track communications and crack down on the flow of arms, fighters and money.
The two retailers have been identified as Lim Geok Kay of Teck Bee Brothers Company at 220 Syed Alwi Road and Chia Thuang Chiew of CPP Trading at Block 731 Yishun Street 72.
The tightening of anti-terrorism laws in the world's largest Muslim-majority country comes as concern grows about the spread of influence of Islamic State.
Deputy Commissioner for International, Investigation and Indirect Taxes Group of the Inland Revenue Authority of Singapore Chia-Tern Huey Min will be signing both agreements in Netherlands.