Joe Walsh, a former Republican congressman from Illinois and conservative radio host, has officially announced a challenge to Donald Trump for their party’s 2020 presidential nomination.

Mr Walsh made the announcement on Twitter, where he specifically attacked Mr Trump, whom he had previously supported in 2016.

“We can’t take four more years of Donald Trump. And that’s why I’m running for president. It won’t be easy, but bravery is never easy. But together, we can do it,” Mr Walsh wrote in his campaign announcement.

The former Republican congressman supported Mr Trump in 2016, but said at the time that he only did so because the future president would otherwise have been Hillary Clinton.

Since he became president, however, Mr Walsh said the president’s behaviour has become increasingly concerning. The moment of no return came when Mr Trump, during a press conference last summer with Vladimir Putin, said that he trusted the Russian leader’s words over American intelligence agency analysis of meddling in the 2016 election.

Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Show all 30 1 /30 Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Members of the Proud Boys, a fascist group, jeer at anti-Trump protesters outside of the president's 2020 campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A supporter dressed as Uncle Sam poses at Uncle Sam Reuters Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A baby blimp rears its head amidst a group of anti-Trump protesters outside the president't campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam President Trump addresses supporters at the launch event of his 2020 election campaign in Orlando, Florida Reuters Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Proud Boys have adopted Fred Perry polo shirts as their uniform and many members have the name of the group tattooed on their arms Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A line of police officers separate opposing groups of protesters outside the launch of President Trump's 2020 campaign launch Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A protester hits a Trump punching bag during a protest outside Trump's 2020 campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Twin Trump supporters pose for a photo at the president's 2020 campaign launch in Orlando, Florida Reuters Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A protester dressed as a caricature of Donald Trump stands outside the president's 2020 campaign launch in Orlando, Florida AP Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A Trump supporter faces off against a protester outside the president's campaign launch in Orlando, Florida AFP/Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A Proud Boy shouts across the police line at anti-Trump protesters outside the president's campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A Trump supporter poses for a photo at the president's 2020 campaign launch in Orlando, Florida Reuters Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A Proud Boy jeers at anti-Trump protesters who are separated from the president's supporters by a police line outside the president's campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A man dressed as Uncle Sam poses at President Trump's 2020 campaign launch in Orlando, Florida Reuters Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam An anti-Trump protester faces off against a supporter outside the president's campaign launch in Orlando, Florida AFP/Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Members of the Proud Boys, a fascist group, jeer at anti-Trump protesters outside of the president's 2020 campaign launch Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A child holds a 2020 US "dollar bill" that features Donald Trump's face at the president's 2020 campaign launch EPA Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Anti-Trump protesters rally outside the president's 2020 campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Anti-Trump protesters rally outside the president's 2020 campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Numerous baby Trump balloons are raised in protests outside of the president's 2020 campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A supporter wears a T-shirt depicting Trump as a hero at the president's 2020 campaign launch in Orlando, Florida Reuters Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam President Trump addresses supporters at the launch event of his 2020 election campaign in the Amway Centre in Orlando, Florida AFP/Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam An anti-Trump protester calls for the president to be impeached outside the launch event for his 2020 campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Supporters of Donald Trump face off against protesters outside of the president's 2020 campaign launch in Orlando, Florida AP Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A baby blimp rises behind a group of anti-Trump protesters outside the president's campaign launch in Orlando, Florida AP Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A supporter dressed as Uncle Sam poses at President Trump's 2020 campaign launch in Orlando, Florida AP Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A member of the Proud Boys, a fascist group, holds a sign up outside of the president's 2020 campaign launch in Orlando, Florida AFP/Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A supporter bears a Trump flag at the president's 2020 campaign launch in Orlando, Florida Reuters Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Protesters hold baby Trump balloons in the rally outside of the president's 2020 campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam An anti-Trump protester holds a sign accusing the president of being a traitor Getty

Mr Walsh is among three Republicans considering a run against Mr Trump for the 2020 nomination, which is expected to be a long-shot bid for any candidate as the president enjoys an 88 per cent approval rating within the party.

Former Massachusetts governor Bill Weld is one of those other Republicans, having announced months ago.

Support free-thinking journalism and attend Independent events