THE Scottish Green Party is to challenge the UK's elections watchdog after it laid down a hefty fine for finance "failures".

The Electoral Commission has ordered Patrick Harvie's party to pay £5,350 for breaching rules on disclosing donations.

The breach is said to have occurred on seven different occasions dating back to 2016 – and totalling almost £52,300.

But the Scottish Greens, co-led by Lorna Slater, say they've declared every penny and should not be forced to pay out for what they say is a "technical" error in their accounts.

The party said: "All monies have been reported in our audited accounts and submitted to the Electoral Commission, so we are disputing this penalty."

A Scottish Greens source said the matter relates to a "sudden" change in tack by the Electoral Commission over "short money", funds that are received from the Scottish Parliament Corporate Body.

It's understood that the Edinburgh-based party was told it has been listing those takings "in the wrong place for a few years".

The watchdog said those 18 cash donations represent 35% of the total value of all donations the Greens should have included in their reports.

A source described this as a "technical error", stating: "Given we’ve reported all our income and the guidance on this was not clear, we are absolutely contesting the decision."

The four-figure sum is more than half of the £8,900 sum declared in donations by the Scottish Greens earlier this month.

The party has until September 24 to make the payment.

The Electoral Commission said: "We impose sanctions for each individual offence committed. The level of each sanction takes into account a number of different factors, including the seriousness and harm caused."

The Greens are one of seven parties and individuals found to be in breach of UK electoral regulations – and had the highest penalty.

The Conservative Party and the Brexit Party were also censured for the "failure to deliver accurate quarterly donations reports" and fined £4400 and £200 respectively.

Boris Johnson's Health and Social Care Secretary Matt Hancock was found to have failed to return a donation from an "impermissible donor" within 30 days of receiving it, but escaped without penalty.

The Commission said there are mitigating factors in his case, which has been closed with no further action taken.

But the DUP's Ian Paisley MP has been fined by the elections watchdog over a finance breach linked to a party fundraiser Michael Gove spoke at.

Tory politician Gove, one of the most senior members of parliament, addressed the DUP event in Northern Ireland three years ago.