WASHINGTON - A US judge has dismissed Mr Donald Trump's lawsuit against his 2016 rival Hillary Clinton, saying the former Republican president's allegations that Democrats tried to rig that election by linking his campaign to Russia was an attempt to "flaunt" political grievances that did not belong in court.

In throwing out Mr Trump's lawsuit Thursday night, Judge Donald Middlebrooks of the US District Court for the Southern District of Florida said the lawsuit was not seeking "redress for any legal harm" and that the court was "not the appropriate forum" for the former president's complaints.

"He is seeking to flaunt a two-hundred-page political manifesto outlining his grievances against those that have opposed him," Mr Middlebrooks said in his ruling.

Mr Trump in March had sued Mrs Clinton, who was the 2016 Democratic presidential nominee, and several other Democrats alleging"racketeering," a "conspiracy to commit injurious falsehood" and other claims in a 108-page lawsuit that echoed the long list of grievances he repeatedly aired during his four years in the White House after beating Mrs Clinton.

He had sought compensatory and punitive damages, saying he had incurred more than US$24 million (S$33.58 million) in "defence costs, legal fees, and related expenses."

In his ruling, Mr Middlebrooks said Mr Trump had waited too long to file his complaint by exceeding the legal statute of limitations for his claims and that he failed to make his case that he was harmed by any falsehoods, noting that many of the statements made by the defendants were "plainly protected by the First Amendment" of the US Constitution.

Representatives for Mrs Clinton and Mr Trump did not immediately respond to a request for comment on the ruling.

Other defendants included Democratic Representative Adam Schiff, who led one of the US House of Representatives' impeachments against Mr Trump, and Mr Christopher Steele, a former British intelligence officer who wrote a dossier circulated to the FBI and media outlets before the 2016 election.

US intelligence officials and others in the US government have accused Russia of meddling in that election. Moscow has denied that it interfered in the campaign. REUTERS