At a summit bogged down by simmering trade tensions, Prime Minister Lee Hsien Loong joined several world leaders in a call to strengthen the global trading system that has helped countries large and small prosper, adding that it was important to get the politics right.
This will help sustain policies that support global trade and investment, which in turn will benefit citizens, he said on the first day of the Group of 20 Leaders' Summit in Osaka.
"Leaders need to explain the challenges and trade-offs clearly and honestly to voters, persuade them, and work together with them to promote their own long-term interests," he added.
PM Lee was one of several leaders, including the host, Japanese Prime Minister Shinzo Abe, to rally against protectionism and stress the importance of free trade. Singapore is one of eight non-G-20 countries invited to this year's meetings.
Mr Abe called on leaders of the world's 20 largest economies to take steps to mitigate the economic risks arising from trade frictions.
"A free and open economy is the foundation of global peace and prosperity," he said. "While anxiety and discontent with abrupt changes due to globalisation can at times generate the temptations for protectionism, bringing about sharp confrontation between states, tit-for-tat trade restrictive measures are to the benefit of no one."
Meanwhile, Chinese President Xi Jinping told a meeting of leaders of the Brics - Brazil, Russia, India, China and South Africa - group of emerging economies that "all this is destroying the global trade order". "This not only impacts the common interests of our countries, but also overshadows global peace and stability," he said.
On the flip side, United States President Donald Trump made clear in separate meetings with Mr Abe and Indian Prime Minister Narendra Modi - ahead of much-anticipated talks with Mr Xi today - that his priority was to conclude trade deals that would benefit the US economy.
Although the G-20 bloc is likely to agree on a generic phrase, "the promotion of free trade", in the final leaders' document to be issued today - doing away with any strong commitment against protectionism - the leaders are still poles apart on how to get there.
PM Lee said the World Trade Organisation (WTO) must be brought up to date, and urged members to "work constructively and urgently undertake reform". This includes resolving the impasse over WTO's appellate body, which hears appeals in trade disputes, where the US has blocked the appointment of judges.
He added that while the existing multilateral trading system is imperfect, the alternative would be much worse. Segments of the population in many countries feel globalisation has worked against them, and are pushing back against it.
"But the solution is not to close up. Instead, we must raise the skills of our people to prepare them for new jobs, and help our businesses to adopt new technologies and to raise productivity," he said. "We must get our politics right too, in order to sustain policies that support global trade and investment, and enable our peoples to benefit from them."
He also spoke of developing new rules for the digital economy, commending Japan on its leadership.
Warning that the consequences of turning away from globalisation will be dire, PM Lee said he looks forward to working with his counterparts on these important issues and injecting new momentum.
"If globalisation does not hold, the world economy will be divided into rival blocs, tensions and conflicts will sap our attention and resources, and we will all be poorer off and less secure," he added.