A website to "fact check" the US president was launched by his Republican opponents just before President Joe Biden announced his eagerly awaited 2024 re-election bid on Tuesday.

The action highlights attempts on both sides of the political spectrum to fire salvos using the fact-checking format at opponents, a move analysts say runs the risk of undermining faith in non-partisan experts who disprove false information.

The Republican National Committee launched Factcheckbiden.com, which is solely dedicated to exposing in real-time, what the party has labeled the president's "lies."

"The RNC will continue to hold Biden accountable for his lies, and in November 2024, the American people will too," RNC chairwoman Ronna McDaniel said in a statement.

The website was launched just one day before Democrat Biden declared his candidacy for a second term in office, setting the stage for a potential rematch with Donald Trump.

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On social media, Trump's Republican backers marketed the website as the "Biden White House's new least favorite website."

With a deluge of posts combining factual links with personal opinions, the website appeared to be pushing Republican talking points—something that expert fact-checkers typically avoid.

Remarks made by Biden were marked as "personal lies," "made-up stories" and, in one instance, a "really, really weird lie."

"This sounds like a fairly standard campaign tactic, to set up a website to 'fact check' statements by your opponent," Joshua Tucker, co-director of the NYU Center for Social Media and Politics, told AFP.

He added that mainstream media sources are going to confuse an RNC site fact-checking Biden for a non-partisan or professional fact-checking site.

'Muddying the waters' 

The Republican action is a reflection of similar Democratic initiatives.

A "war room" that regularly sends out email newsletters with "fact-checks" or criticisms of Republican politicians has been established by the Democratic National Committee.

Hillary Clinton's personal website conducted a live "fact-check" of Donald Trump during a 2016 presidential debate in which the two candidates faced off.

Clinton urged viewers of the debate to visit the segment called "Literally Trump" to witness the facts – a call that attracted millions of hits in a short span, according to US media.

During Trump's 2017–2021 presidency, fact-checking by reputable media outlets was a perpetually hectic exercise as his every word and tweet – frequently rife with inaccuracies – was closely examined.

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