You should really not cut out the words like the Western MSM do ... the deliberate omission and/or the spins & twists
"...rules-based international order in the region, based on international law, where all countries can both cooperate and compete peacefully with one another, and prosper together"
Have you ever heard such phrase -- "rules-based international order in the region, based on international law" -- from any Washington guy???
By common English language, it's obvious from the line that the "international law" takes subset of the "rules-based international order" so whatever Mr. Lee wanna convey to amuse the ears of his guests.
I think it was deliberate. He wanted to emphasize the rule-based international order should be based on international law (Emphasized LAW).
And not (Anglo's perception of rule)-based international order.