NIGEL FARAGE’S new Brexit Party is facing an investigation into its finances after Gordon Brown suggested it may be receiving illegal foreign donations.

The Electoral Commission will today visit the party’s offices to review its funding operation, just 48 hours before the European election it is expected to win UK-wide.

Polls suggest it will also comfortably win one of the six seats in Scotland.

READ MORE: Gordon Brown calls for urgent investigation into Brexit Party’s ‘dirty money’

The dramatic development followed the former Labour prime minister warning that foreign donors could be bankrolling the party through the online system PayPal, and hence influencing Thursday’s result.

Urging the Commission to investigate “the finances of Nigel Farage and the Brexit Party” in a speech in

Glasgow yesterday, he said: “Democracy is undermined when we have undeclared, unreported, untraceable payments being made to the Brexit Party. We have the potential for underhand and under-the-counter payments being made.”

He said Mr Farage and the Leave campaign of 2016 had form on questionable finances, with three investigations into the EU referendum.

Within hours, the Commission said it would visit the Brexit Party’s offices as part of “active oversight and regulation” of the ban on single and cumulative foreign donations above £500.

Mr Farage, who had a milkshake thrown at him while campaigning in Newcastle yesterday, accused Mr Brown of an “absolutely disgusting smear” against his party.

He said: “This from the man who was part of a Labour Party who, through Lord Levy, were making a lot of big donors members of the House of Lords. How dare he?

“Most of our money has been raised by people giving £25 to become registered supporters and nearly 110,000 of them now have done that. Frankly, this smacks of jealousy because the other parties simply can’t do this.

“What you have got here are the conspiracy theorists doing their utmost to try and de-legitimise what is the

fastest-growing political movement this country has ever seen.”

However, on BBC Radio 4, Brexit Party chairman Richard Tice refused to say if any of the £2.5 million in small donations so far had included foreign money, instead attacking “jealous” critics.

On being doused in a £5.25 banana and salted caramel milkshake, Mr Farage said some Remainers had been “radicalised”, and normal campaigning was becoming impossible.

Former PM Tony Blair said the milkshake incident was “horrible and

ridiculous”, tweeting “I can’t stand this”, and adding that Mr Farage was entitled to his point of view.

Brendan Cox, whose wife Labour MP Jo Cox was murdered during the EU referendum, said he disliked Mr Farage’s politics “profoundly”, but throwing things at politicians only normalised violence and intimidation and should be opposed.

Northumbria Police later said a 32-year-old man had been arrested on suspicion of common assault.

Mr Brown called for the investigation at a Scottish Labour event in which he launched a sustain attack on Mr Farage, but failed to mention Jeremy Corbyn.

He told party activists the Brexit Party was not a true political party, but a private company in which Mr Farage was the key shareholder with the controlling interest.

He said: “You pay money not to become a member, but to become a supporter, and you pay through PayPal and you cannot discover whether the money is coming from foreign sources or British sources.

“Indeed, you can pay to this party in Russian roubles, American dollars, Malaysian ringgits and, of course, probably to his disdain, euros as well.”

He added: “This is a not a party in the ordinary sense, this is a private company. It’s run by Nigel Farage, donations go through PayPal, and he’s not going to be remembered as he wants, as the man of the people. He’ll be remembered as the man of the PayPal, because that’s where the money’s coming from.”

Referring to the Leave campaign’s “history” of financial issues, fines and investigations, he said: “Aaron Banks, the lead funder of Leave.EU and the friend of Nigel Farage has been under investigation - he has made contacts with Russia. We don’t know where his money comes from.

“And yet we find out last week that he has given £450,000 in payments to support Nigel Farage, while Nigel Farage was in a public office in the European Parliament, who should have been declaring the payments that he was receiving from anyone to avoid any conflicts of interest.”

Mr Brown also accused the SNP and Tories of becoming more “extreme” and of preferring an endless Punch and Judy Show over the constitution to practical, sensible policies.

READ MORE: Nigel Farage hit by milkshake during campaign walkabout

He said the SNP’s policy of adopting a new currency “as soon as practicable”after independence, subject to six tests, was “far more extreme” than its 2014 plan to share the pound.

He said: “If you vote for the SNP on Thursday, you’re voting to give recognition and legitimacy and credibility to a more extreme form of independence than ever we’ve seen.”

He said the Tories were also guilty of “a more extreme version of centralisation than ever before” by delaying the return of powers from Brussels to Holyrood.

None of the other five speakers at the event mentioned Mr Corbyn either, despite his face adorning Scottish Labour’s election leaflets instead of Scottish leader Richard Leonard.

The Herald: Former prime minister Gordon Brown spoke at the Scottish Labour rally in GlasgowFormer prime minister Gordon Brown spoke at the Scottish Labour rally in Glasgow

Labour MEP David Martin, who is at the top of his party’s Scottish list, instead praised Mr Brown, “who never fails to provide leadership and inspiration when we need it most”.

Glasgow Tory MSP Annie Wells said: “This event shows just how detached from reality the Labour party are.

“Now the respective parties north and south of the border don’t even acknowledge each other in public.

“It’s no wonder they’re becoming such an irrelevance in Scotland.”

SNP Euro candidate Christian Allard said: “People in Scotland remember Gordon Brown as playing a key role in the campaign to ensure that we would continue having to live under Tory governments we didn’t vote for - and now that Tory Government is trying to drag Scotland out of the EU against our will.

“If he wants people to even consider listening to Labour on anything, Mr Brown should start by apologising to Scotland for the mess he has helped create.”

Scottish LibDem MSP Alex Cole-Hamilton MSP added: “Cometh the hour, cometh the Gordon Brown intervention. Sadly even he is too late to save the Scottish Labour ship.

“It’s still not clear whether Scottish Labour want a People’s Vote or whether they are backing a red Brexit. This mealy mouthed approach will cost them dear.”

The Electoral Commission said the Brexit Party, like all registered parties, had to comply with laws on only accepting donations over £500 from permissible sources and on reporting its income.

A spokesperson said: “We have already been talking to the party about these issues. As part of our active oversight and regulation of these rules, we are attending the Brexit Party’s office to conduct a review of the systems it has in place to receive funds, including donations over £500 that have to be from the UK only.

“If there’s evidence that the law may have been broken, we will consider that in line with our Enforcement Policy.”