After media outlets declared the former US vice-president winner of the presidential election, Joe Biden delivered a speech saying he wishes to unify the country and will not treat opponents as enemies while incumbent President Donald Trump's camp sought legal solutions to the election controversy, which is yet to be resolved as the official result is still awaited.

Many in the United States may not take Biden's message to heart. But governments around the world－including the American government－should consider the message seriously when conducting their foreign policies. For the US, Biden's remarks about not treating opponents as enemies, ending an era of demonizing others and lowering the political temperature will be critical to its foreign policy toward China.

For the new US administration, domestic challenges will be the priority, which include containing the COVID-19 pandemic, stimulating the economy, and working to restore the social order in the aftermath of the Black Lives Matter protests. This is a tall order for any leader beginning his term as a country's president.

But the world's problems won't wait for the US to get its house in order, and the US has an important role to play in helping resolve global issues. The best way for the US to be a positive force in world affairs, given that it is gripped by divisions at home, would be to partner with China through a new doctrine of engagement.

Hawks and traditionalists on either side may view this as utopian, but it will be in the interest of the US to win more friends, especially in Asia which would like to see Washington and Beijing work for the betterment of the region rather than be forced to choose between the two sides.

From fighting climate change to controlling the pandemic, and from strengthening nuclear non-proliferation to peacekeeping, a post-pandemic world will need all countries to work together－even those that may compete in some areas or disagree on a number of key issues.

Biden has already signalled a more cooperative relationship with the rest of the world, saying the US will rejoin the World Health Organization. He has also said Washington will rejoin the Paris Agreement on the first day of his term in office. In general, we can expect a more cohesive and conciliatory US approach to the rest of the world, even toward countries that compete with the US in some spheres.

And the key to this new development will be the relationship between China and the US. The Donald Trump administration seems hell-bent on sparking tensions rather than working to resolve the differences and conflicts between the US and China.

But much as we say the US must take a less aggressive stance when it comes to its differences with China and that it cannot solve major global problems without China, we should also realize that China, too, cannot solve these problems without the US.

The role of the two countries in global affairs will depend on cooperation rather than conflict. Both stand to lose as will the rest of the world if the China-US conflicts and differences intensify. And the two sides owe the resolution of burning global issues to the world.

As for the areas of cooperation, climate change readily comes to mind. As the world's two largest economies, it is incumbent upon both the US and China to get a handle on their carbon emissions and resource consumption. Working together, they can help the countries which need financial and technological assistance, especially in Asia and Africa.

The other areas they can cooperate on include denuclearization of the Korean Peninsula, and the Middle East crisis. These are issues that need delicate handling to ensure they don't spiral out of control.

Then there are areas in which the interests of Beijing and Washington are in competition, if not conflict, but where discussions can pave the way for "rules of the road" to be framed－disputes in the South China Sea or discussions on technological progress, for example.

There are many things the US and China will disagree on, not least because there is still a great deal of mistrust between the two sides, which is unlikely to evaporate any time soon. But there is a lot more to be gained through cooperation, and this is the moment to write a new chapter.

Therefore, the two sides should start a productive conversation, communicate their views candidly on issues of contention, and understand in which areas they can and need to work together. There is still enough goodwill left in the more than four decades of Sino-US relationship, and that is good enough reason to resume talks.

The author is the founder and CEO of The Global Institute for Tomorrow, an independent think-tank based in Hong Kong.