Political groups that break the law should be slapped with unlimited fines to stem the influence of “dirty money and dodgy data misuse” in UK elections, MPs have said.

A new report by the All-Party Parliamentary Group for Electoral Campaigning Transparency warned that British elections were open to abuse due to outdated electoral laws and called for an end to the cap on fines for breaches of the rules.

The penalty for breaking strict spending laws is £20,000, a sum the head of electoral watchdog said was seen by some donors as “just the cost of doing business”.

Vote Leave, the official Brexit campaign, was fined over breaches to spending limits during the EU referendum in 2016, prompting concerns from some pro-EU groups about the integrity of the result.

Cross-party MPs suggested a new Office for Election Integrity aimed at “stopping rule-breakers slipping through the regulatory gaps”, as well as an end to the cap on fines for breaching electoral law.

Bizarre: Boris Johnson drives 'Brexit' digger through boxes Show all 8 1 /8 Bizarre: Boris Johnson drives 'Brexit' digger through boxes Bizarre: Boris Johnson drives 'Brexit' digger through boxes Conservative party leader Boris Johnson drives a JCB through a fake wall POOL/AFP via Getty Images Bizarre: Boris Johnson drives 'Brexit' digger through boxes Prime Minister Boris Johnson during a visit to JCB cab manufacturing centre in Uttoxeter, while on the General Election campaign trail. PA Photo. Picture date: Tuesday December 10, 2019. See PA story POLITICS Election. Photo credit should read: Stefan Rousseau/PA Wire Stefan Rousseau PA Bizarre: Boris Johnson drives 'Brexit' digger through boxes Britain's Prime Minister and Conservative party leader Boris Johnson drives a Union flag-themed JCB, with the words "Get Brexit Done" inside the digger bucket, through a fake wall emblazoned with the word "GRIDLOCK", during a general election campaign event at JCB construction company in Uttoxeter, Staffordshire, on December 10, 2019. - Britain will go to the polls on December 12, 2019 to vote in a pre-Christmas general election. (Photo by Ben STANSALL / POOL / AFP) (Photo by BEN STANSALL/POOL/AFP via Getty Images) BEN STANSALL AFP via Getty Bizarre: Boris Johnson drives 'Brexit' digger through boxes Prime Minister Boris Johnson sits in a cab of a JCB during a visit to its cab manufacturing centre in Uttoxeter, while on the General Election campaign trail. PA Photo. Picture date: Tuesday December 10, 2019. See PA story POLITICS Election. Photo credit should read: Stefan Rousseau/PA Wire Stefan Rousseau PA Bizarre: Boris Johnson drives 'Brexit' digger through boxes Britain's Prime Minister and Conservative leader Boris Johnson drives a Union flag-themed JCB, with the words "Get Brexit Done" inside the digger bucket, through a fake wall emblazoned with the word "GRIDLOCK", during a general election campaign event at JCB construction company in Uttoxeter, Britain, December 10, 2019. Ben Stansall/AFP/Pool via REUTERS POOL REUTERS Bizarre: Boris Johnson drives 'Brexit' digger through boxes A sign made for a visit by Prime Minister Boris Johnson to the JCB cab manufacturing centre in Uttoxeter, while on the General Election campaign trail. PA Photo. Picture date: Tuesday December 10, 2019. See PA story POLITICS Election. Photo credit should read: Stefan Rousseau/PA Wire Stefan Rousseau PA Bizarre: Boris Johnson drives 'Brexit' digger through boxes Britain's Prime Minister and Conservative party leader Boris Johnson drives a Union flag-themed JCB, with the words "Get Brexit Done" inside the digger bucket, through a fake wall emblazoned with the word "GRIDLOCK", during a general election campaign event at JCB construction company in Uttoxeter, Staffordshire, on December 10, 2019. - Britain will go to the polls on December 12, 2019 to vote in a pre-Christmas general election. (Photo by Ben STANSALL / POOL / AFP) (Photo by BEN STANSALL/POOL/AFP via Getty Images) BEN STANSALL AFP via Getty Bizarre: Boris Johnson drives 'Brexit' digger through boxes Britain's Prime Minister and Conservative party leader Boris Johnson reacts as he sits in the cab of a drives a Union flag-themed JCB, after driving through a fake wall emblazoned with the word "GRIDLOCK", during a general election campaign event at JCB construction company in Uttoxeter, Staffordshire, on December 10, 2019. - Britain will go to the polls on December 12, 2019 to vote in a pre-Christmas general election. (Photo by Ben STANSALL / POOL / AFP) (Photo by BEN STANSALL/POOL/AFP via Getty Images) BEN STANSALL AFP via Getty

Moves need to be made to “close foreign donor loopholes” by ensuring all donations have to be UK-based and powers must be given to the Electoral Commission to allow it to launch prosecutions, the report added.

Labour MP Stephen Kinnock, who chairs the group, said: “The outdated nature of UK election law has pitched us into a battle for the very soul of our democracy.

“Facebook and other digital giants now play a hugely significant role in our elections and referendums, but most of the current legislation was created before the phrase ‘social media’ even existed.

“It was in 2018 that the cracks in our democratic processes really started to show, when former chief executive of the Electoral Commission, Claire Bassett, told the Digital, Culture, Media and Sport select committee the current maximum per-offence fine of £20,000 was – for political actors – no more than ‘a cost of doing business’.

“Now, nearly four years on from the EU referendum, absolutely nothing has been done to protect our system from dodgy money and dirty data.​”

Green MP Caroline Lucas said the law-breaking over spending limits exposed vulnerabilities in the system.

“Both Leave campaigns broke spending limits but the fines available to the Electoral Commission were derisory,” she said.

“We are used to some political parties having much deeper pockets than others.