A former US governor has become the first Republican politician to challenge Donald Trump for the presidency.
Bill Weld, who served as governor of Massachusetts during the 1990s, announced he had formed a presidential exploratory committee to challenge President Donald Trump in the 2020 Republican primaries.
Weld, who rejoined the party this year after campaigning as the Libertarian party’s vice-presidential candidate in 2016, attacked Trump’s record in a speech at a breakfast event in Bedford, New Hampshire.
"It is time for all people of good will to take a stand and plant a flag," he said.
"It's for this reason that I have today established an Exploratory Committee to pursue the possibility for my running for the Presidency of the United States as a Republican in the 2020 election."
An incumbent president rarely faces a major challenger to their renomination as the party’s presidential candidate but these challenges can inflict major reputational damage in main electoral race.
Few Republicans have been willing to criticise Trump openly because of the loyalty he has from his base supporters, but he remains one of the most unpopular incumbent presidents of all time, with an average job approval rating of 39% since taking office according to Gallup.