A FOUNDER of the Leave.EU campaign is being investigated for “suspected criminal offences” over £8 million of campaign funding during the Brexit referendum.

The National Crime Agency (NCA) launched a probe after the Electoral Commission said it had reasonable grounds to suspect that Arron Banks was not the true source of the cash.

However, Banks said he was confident the investigation would “put an end to the ludicrous allegations” against him.

The watchdog also referred Leave.EU, its chief executive, Elizabeth Bilney, and the organisation that ran it, Better for the Country, to the NCA after carrying out a review.

Bob Posner, director of political finance, said: “We have reasonable grounds to suspect money given to Better for the Country came from impermissible sources and that Mr Banks and Ms Bilney ... knowingly concealed the true circumstances under which this money was provided.

“This is significant because at least £2.9m of this money was used to fund referendum spending and donations during the regulated period of the EU referendum.

“Our investigation has unveiled evidence that suggests criminal offences have been committed which fall beyond the remit of the commission ... This is now a criminal investigation. The financial transactions we have investigated include companies incorporated in Gibraltar and the Isle of Man. These jurisdictions are beyond the reach of the Electoral Commission for the purpose of obtaining information for use in criminal investigations or proceedings.”

Banks said the commission had referred him to the NCA under “intense political pressure” from anti-Brexit supporters.

“I am confident that a full and frank investigation will finally put an end to the ludicrous allegations levelled against me and my colleagues,” he said.

Bilney also accused the commission of having a “biased approach” in its investigations and said she was confident she would be “exonerated”.

She told BBC Radio 4’s World at One: “I hope that the matter will be shortly concluded to demonstrate that no crimes have been committed. They are looking at it how they want to through their own biased lens.”

The Electoral Commission’s review focused on £2m reported to have been loaned to Better for the Country by Banks and his insurance companies and a £6m donation he made alone.

An NCA spokesman said: “While electoral law offences would not routinely fall within the NCA’s remit, the nature of the necessary inquiries and the potential for offences to have been committed other than under electoral law lead us to consider an NCA investigation appropriate in this instance.”

Meanwhile, Scottish Secretary David Mundell has ruled out the UK staying in the Commons Fisheries Policy any longer than planned. He told BBC Scotland the country would be an “independent coastal state” in December 2020 even if the post-Brexit transition period was extended from next March.