We believe that the World Trade Organization, despite its limitations, is best positioned to address China’s trade practices. We also believe that the W.T.O. is the most appropriate forum in which to resolve trade disputes. So we urge the United States and China to work with other member states to strengthen the W.T.O.’s institutional capacity.

Our group of former prime ministers and presidents includes François Fillon of France, Joe Clark of Canada, Enrico Letta of Italy, Jan Peter Balkenende of the Netherlands, Felipe Calderón and Ernesto Zedillo of Mexico, and Han Seung-soo of South Korea. Given our collective experience, we are not naïve about the inherent complexities in negotiating trade agreements. Many of us have negotiated free-trade pacts with both the United States and China. We are deeply familiar with the concerns of each country, including the domestic political constituencies that argue for continued protection.

Many of those domestic concerns have focused on the long-term enforcement of any agreement. On this point, we argue that it is in China’s own long-term economic interest to ensure the effective implementation of any new trade deal — whether involving intellectual property, technology transfer, state subsidies or market access. Such policies would also need to apply to all of China’s trading partners, just as they would need to apply to its relationship with the United States.

On the question of enforcement, China must be acutely aware that if it fails to comply with the terms of the agreement, an already damaging trade war is likely to resume. A new trade agreement should include strong enforcement provisions, along with strengthened W.T.O. dispute-resolution mechanisms, to give greater confidence to both parties.

For these reasons, and given the gravity of the global economic outlook for 2020, we urge both countries to exercise every effort to reach a substantive agreement this year. We also urge the United States to withdraw the punitive tariffs it has imposed — and that China do the same with the reciprocal tariffs it has enacted.

Beyond trade, we are anxious about the wider strategic impact of any further decoupling of the Chinese and the American economies, particularly in technology and finance. Such a decoupling would present a long-term threat to global peace and security.

It would also effectively constitute the first step in the declaration of a new Cold War. As with the last Cold War, many nations would be forced to choose between the two powers. And that is a choice none of us wants to make.