Hello, I'm Rosakins.

Each week on the BBC World Service, I look at one of the biggest issues in the news.

This time, it's climate commitments.

We're all going to be dealing with this certainly for the rest of our lives.

This challenge is as big as any that we face on a global basis.

In China, my friend plays a super critical role.

This is the US climate envoy, John Kerry.

And as he points out, China plays a critical role in taking on climate change.

So too, does America.

They are two of the world's biggest emitters of greenhouse gases.

And while climate change is a global problem that requires a global solution,

in reality, the biggest emitters can have the biggest impact.

President Biden understands that.

The United States sets out on the road to cut greenhouse gases in half,

in half by the end of this decade.

China, too, acknowledges the need to act.

But there are tensions over which countries should pay for the rapid change that's needed.

This is China's president, Xi Jinping.

Developer countries need to increase climate ambition and action,

and make concrete efforts to help developing countries accelerate the transition

to green and low carbon development.

As you can hear, there's disagreement over who bears the cost of climate policies.

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