Donald Trump predicts he'll be re-elected in 2020 with increased majority

President Donald Trump gestures to the cheering audience as he arrives to speak at the Conservative Political Action Conference Credit: Carolyn Kaster/AP

Donald Trump has predicted he will win re-election in 2020 - and with a bigger a margin than in 2016.

In a speech at the Conservative Political Action Conference, the US President also mocked Democrats for their framework to combat climate change and said House politicians pushing to expand their investigations of him are "sick".

When he made his prediction of a second term, the Maryland crowd responded with chants of "USA, USA, USA."

Mr Trump praised the conservative movement, saying "Our movement and our future in our country is unlimited."

He took aim at the Democrats’ Green New Deal, a policy proposal floated by some liberal Democrats in Congress and backed to varying degrees by several of the party's 2020 presidential candidates.

"I think the New Green Deal, or whatever the hell they call it — the Green New Deal — I encourage it," Mr Trump said mockingly.

"I think it'"s really something that they should promote. They should work hard on it… No planes, no energy. When the wind stops blowing that’s the end of your electric. Let’s hurry up, darling, is the wind blowing today? I’d like to watch television, darling."

Mr Trump predicted he would be victorious again. Credit: AP

The Democrat plan calls for a drastic drop in greenhouse gas emissions from fossil fuels such as oil, coal and natural gas, but in no way grounds planes or pivots the country to renewable energy only.

With special counsel Robert Mueller’s Russia investigation seemingly approaching its end, Mr Trump spoke of the “collusion delusion” and lashed out at newly empowered House Democrats who are opening new inquiries involving him.

He said of the Russia probe: "This phoney thing looks like it’s dying so they don’t have anything with Russia there, no collusion. So now they go in and morph into ‘Let’s inspect every deal he’s ever done. We’re going to go into his finances. We’re going to check his deals. We’re going to check…’ – these people are sick."

House Democrats are undertaking several broad new investigations that reach far beyond Mr Mueller’s focus on Russian interference in the 2016 election and possible collusion between Russians and the Trump campaign.

Mr Mueller has not yet brought any public charges alleging a criminal conspiracy between the campaign and Russia, and the investigation continues.

Their efforts increased this week after Mr Trump’s former personal lawyer Michael Cohen appeared before two House committees and a Senate committee.

In his public testimony before the House Oversight and Reform Committee, Mr Cohen called the president a "con man" and a "cheat" and gave Democrats several new leads for inquiry.