Former New Jersey Governor Chris Christie launched his 2024 U.S. presidential campaign, starting it with a scathing attack on Donald Trump and blaming other rivals for avoiding a direct confrontation with him.

Christie presented himself as the only Republican challenger willing to confront Trump. He is one of the former president's most vocal critics for allegedly falsifying the result of the 2020 presidential election.

"A pig who is busy with himself and serving his interests is not fit as a leader," he said.

Christie mocked Trump when he said he would build a border wall in the south of the country that Mexico would afford, and argued that the former president bears more responsibility than current Democratic President Joe Biden for the failure of immigration policy.

Mutual criticism

Trump traded criticism with Christie, referring – in a post on the social media site founded by Truth Social – to the weight of his rival, calling him a "failed governor."

Christie has not found much luck in the polls so far, winning the support of just 1% of likely voters in the Republican primary in a Reuters/Ipsos poll in May, compared with Trump, who won 49%, and Florida Governor Ron DeSantis, who received 19% support.

Other Republicans seeking the Republican nomination to run against Biden include former U.S. Ambassador to the United Nations Nikki Haley and Senator Tim Scott.

Former Trump Vice President Mike Pence is scheduled to announce his candidacy on Wednesday.

Christie, a former federal prosecutor, ran in the 2016 election but ended his campaign after a disappointing result in the New Hampshire primary, becoming the first senior party figure to support Trump and becoming a campaign adviser.

But he later disavowed Trump, a change that would appeal to Republicans who want to turn the page on the former president. But it remains unclear whether any Republican challenger can dominate the crowded arena without support from a base that remains loyal to Trump.