With Musk named to a new position in the incoming US administration of Donald Trump, there are fears the world's richest man could seek to influence London's future ties with Washington.
On Wednesday, Farage, who leads the upstart anti-immigration Reform UK party, said he was in talks with Musk about making a donation to his party.
Writing in the Telegraph newspaper, Farage said "the issue of money was discussed" when he met the X owner at Trump's Mar-a-Lago resort in Florida on Monday.
"There will be ongoing negotiations on that score," the arch-Eurosceptic wrote, in comments that will likely unnerve the ruling Labour party and main Conservative opposition.
Newspaper reports have suggested that Musk is preparing to donate up to $100 million to Reform but Farage told the BBC the pair did not discuss figures.
Musk "described the Labour and Conservative parties as the uniparty, and left us in no doubt that he is right behind us", Farage added.
Farage said they would have to find a way to ensure any donation from Musk was made "legally through UK companies" but the idea which emerged a few weeks ago has already sent shivers down the spines of UK lawmakers.
Reform UK won five seats in the 650-seat UK parliament in July's general election, draining support from both Labour and the Tories.
'Police state'
Farage is already eyeing the next general elections, which have to be held by 2029 at the latest.
Conservative party co-chairman Dominic Johnson said any such donation by Musk would be "basically buying" one of the UK's political parties.
"People like Elon Musk, like Donald Trump, like Nigel Farage ... the sort of the new right, they really hate the old right" which is seen as having become too liberal, said Russell Foster, senior lecturer in British and International politics at King's College.
This old right "were not killed off by the left or centre. They're killed off because a more right-wing movement comes along".
So far, Musk has contented himself with taking aim at the Labour government of Prime Minister Keir Starmer, launching a series of searing comments on his social network X.
"The people of Britain have had enough of a tyrannical police state," he stormed in November.
At the height of this summer's anti-immigrant riots -- the UK's worst unrest in years -- Musk wrote in X that "civil war is inevitable" and accused the government of dealing with the rioters too harshly.
It won him support among UK social network users and influencers on the far-right.
Musk also advised people in September not to visit the UK when "they're releasing convicted pedophiles in order to imprison people for social media posts".
"He appears to believe that he is on some sort of a mission against the establishment," said Foster.
Pragmatism
Some observers believe Musk is also up in arms about UK government plans to toughen legislation regulating social networks.
Starmer said the riots had been fuelled by online content and later did not invite Musk to an investors' conference -- something the SpaceX and Tesla CEO had taken as an insult, sources close to him said.
Since the US presidential elections, Musk and Trump have become inseparable, and their "bromance" could complicate Labour's efforts to boost its ties with the Republicans.
Labour has historically been closer to the Democrats but Starmer, who met Trump in New York in September, has been seeking to open a new chapter in the party's relations with Republicans.
"The prime minister looks forward to working with President Trump and his whole team, including Elon Musk," a Downing Street spokesman said last month.
"Starmer is very aware that he can't alienate the incoming US president," said Foster.
"We think that we have to maintain that special relationship. So it doesn't matter who's in the White House, we're always going to be nice towards Washington."
Labour politician and former cabinet minister Peter Mandelson said it would be "unwise" for the UK to ignore Musk, calling on the Labour party to "swallow your pride."
He described Farage as a "bridgehead, both to President Trump and to Elon Musk and others. You've got to be pragmatic, practical about this".
