For a small country like Singapore, our domestic and foreign policies are inextricably linked.
"Foreign policy allows us to create opportunities for Singaporeans. And domestic policy prepares Singaporeans to seize these opportunities. Both go hand-in-hand to advance the interests of Singapore and Singaporeans," Dr Tony Tan said.
He was speaking at the 10th S Rajaratnam lecture on 28 November.
Singapore cannot rely on having friendly relations to safeguard our national interests and sovereignty.
Singapore has resolutely pursued an independent foreign policy in which our interests are not subservient to anyone else, Dr Tan said.
Diplomacy is not to be confused with foreign policy. Diplomacy is a tool of foreign policy.
Diplomacy is not about having friendly relations 'at all costs'.
Diplomacy is about "promoting friendly relations as a way to protect and advance our own important interests."
Singapore must stand firm to preserve our fundamental interests. Even when we come under 'heavy pressure', Singapore "should not shy away from standing up for our vital interests, even if things inevitably turn sour for a while."
Dr Tan also said we should not seek to appease or ride on the bandwagon for fear of retaliation, especially when Singapore's vital interests are at stake.
"At the end of the day, our policy decisions must be based on one simple question – is this in Singapore’s interest? Where possible, we should try to find a mutually beneficial approach to resolve issues," said Dr Tan.