Former US President Donald Trump has sued Hillary Clinton and several other Democrats, accusing them of trying to rig the 2016 US presidential election by linking his campaign to Russia.

Mr Trump beat Mrs Clinton in 2016.

But he alleges "racketeering" and other claims, as part of an "unthinkable plot" to undermine his campaign.

Mr Trump's campaign and transition teams were accused of conspiring with Russian agents to influence the election in his favour.

A report released by a Republican-led US Senate committee in 2020 concluded that Russia used Republican political operative Paul Manafort and the WikiLeaks website to try to help Mr Trump win. Moscow denies any involvement.

The report stated that no evidence of a conspiracy was found, but it did lay out instances where the president possibly obstructed justice.

Donald Trump has repeatedly claimed there was a Democratic conspiracy to undermine his presidency by suggesting his campaign had nefarious ties to Russia. Now he's putting his lawyers where his mouth is.

The lawsuit - against members of the Clinton campaign and senior FBI officials - is a decided longshot, in part because there is ample evidence of connections between the Trump campaign and Russian operatives as documented by Robert Mueller's special counsel investigation and a report by the bipartisan Senate intelligence committee.

The evidence includes the 2016 Trump Tower meeting between senior campaign staff and Russian nationals and contacts Trump campaign manager Paul Manafort had with a suspected Russian intelligence operative. While that did not lead to charges of criminal collaboration between Mr Trump's team and Russia, it could undermine Mr Trump's allegations that the Clinton team invented the Trump campaign's Russia connections out of whole cloth.

A court victory may be unlikely, but Mr Trump can tout the lawsuit itself to his supporters as evidence that he is fighting back against his accusers. And if the case is eventually dismissed, it will be cited as a sign the establishment is still out to get him.

Mr Trump's legal complaint alleges that "in the run-up to the 2016 presidential election, Mrs Clinton and her cohorts orchestrated an unthinkable plot - one that shocks the conscience and is an affront to this nation's democracy.

"Acting in concert, the Defendants maliciously conspired to weave a false narrative that their Republican opponent, Donald J Trump, was colluding with a hostile foreign sovereignty."

Mrs Clinton is yet to comment on the lawsuit, which seeks compensatory and punitive damages. Mr Trump said he was forced to incur expenses in excess of $24m (£18m).

Former Democratic National Committee chairwoman Debbie Wasserman Schultz, former FBI Director James Comey and Democratic political consultant John Podesta are among others named in the complaint.

Russia's alleged election interference resulted in a two-year-long investigation headed by Special Counsel Robert Mueller.

Mr Mueller did not determine that Mr Trump or his campaign had colluded with Russia, but the special counsel said his report did not exonerate the president of obstruction of justice.

In his report he stated that "the Russian government perceived it would benefit from a Trump presidency and worked to secure that outcome, and that the campaign expected it would benefit electorally from information stolen and released through Russian efforts".