President Donald Trump has officially launched his 2020 re-election bid, urging supporters to “keep this team in place” for four more years.

He made his case before thousands of supporters at a rally in Orlando, Florida, calling the state “my second home”.

The Republican president used the announcement to lash out at Democrats, accusing them of trying to “rip your country apart”.

Early polls place Donald Trump behind some potential Democratic challengers.

The president entered the stage with his wife, Melania Trump, who said she was “excited” to be first lady for six more years.

Senior figures from the White House, including VP Mike Pence and outgoing press secretary Sarah Sanders, also spoke at the rally.

President Trump told supporters: “Tonight I stand before you to officially launch my campaign for a second term as president of the United States.

“I promise you I will never ever let you down.”

Florida is a key battleground state and one that Donald Trump narrowly won in 2016.

“We are going to keep America great again,” President Trump told the Orlando event on June 18, in a reworking of his familiar slogan.

Some supporters had been waiting since the early hours of Monday morning to see the president.

A counter-demonstration against his appearance was also held nearby.

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During his roughly 80-minute speech, President Trump reiterated key themes of his winning 2016 campaign.

The president pledged to continue a crackdown against illegal immigration, one day after tweeting that US Immigration and Customs Enforcement (ICE) would soon begin removing “millions of illegal aliens” from the country.

He told Florida supporters: “We believe our country should be a sanctuary for law-abiding citizens, not for criminal aliens.”

Donald Trump also accused Democrats of seeking to legalize illegal immigration in order to boost their voting base, and said they “want to destroy our country as we know it”.

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President Trump described his opponents as a “radical left-wing mob” who he said would bring socialism to the US.

He told the crowd: “A vote for any Democrat in 2020 is a vote for the rise of radical socialism and the destruction of the American dream.”

President Trump also praised the economy, criticized the Mueller investigation into alleged collusion between the 2016 Trump campaign and Russia, and referred to media covering the event as “fake news back there”.

Donald Trump also elicited “lock her up” chants from supporters when he brought up Hillary Clinton, despite her not being in the 2020 race.