The US will attempt to re-assert its global leadership on climate change as President Joe Biden hosts 40 leaders at a virtual summit in the White House. It is a good time to claim back what Donald Trump had squandered away. 
  
The US will unveil an updated carbon pledge that will see its emissions nearly halved by 2030. 

President Xi Jinping will elaborate on some of the additional efforts that China would choose to make 

Both Brazil and Australia will find it difficult to live with a new approach on climate change by Biden House. 

The challenge is ensuring scientifically credible things have to be politically achievable 

While the Democrats have a majority in the House of Representatives, the Senate is essentially deadlocked, making the passage of new climate legislation rather tricky. 

For some in the international community, even the mooted 50% cut in emissions won't be going far enough. That means the US should cut at least 55% from 2005 levels by 2030 to inspire others to raise their ambitions. 

Canada, Japan and South Korea will give maximum support to Biden. 

This is the first big climate meeting of a critical year that will culminate in a gathering of around 200 world leaders in Glasgow in November at COP26.