Donald Trump is set to mark a key reversal in policy from the Obama administration by denouncing climate change as a possible threat to the US.

The president is due to announce what he perceives to be the biggest threats to the US as part of the National Security Strategy.

In 2010, Barack Obama identified climate change as a key danger to parts of the US, but Trump is set to reverse that decision.

Instead, Trump is poised to place the American economy on the threatened list, suggesting that the US needs to regain its economic competitiveness across the globe.

This however would appear to go against the views of Trump's defence secretary James Mattis, who said in March that "climate change is impacting stability in areas of the world where our troops are operating today".

Studies suggest that large parts of several US states could be threatened by rising ocean waters.

These areas include parts of Florida, Texas, Louisiana, California, New Jersey and New York, all low-lying coastal states.

Earlier in the year, world leaders denounced Trump when he pulled the country out of the Paris Climate Accord.

Both Mattis and the secretary of state are thought to have both voiced their concerns over the US exit from the agreement.

Reacting online, social media users were unhappy with Trump's latest move.

Donald Trump
US President Donald Trump gestures during a joint press conference with Japanese Prime Minister Shinzo Abe at Akasaka Palace JIM WATSON/AFP/Getty Images

Vonnie May on Twitter said: "What a joke national security strategy."

While MomBlogsBest wrote: "HE is our greatest threat to national security. Hands down."

And Dea wrote: "This man in undermining our economy, our infrastructure, our place internationally, and our national security. The question is, why? And why are so many letting him do it?"