Police are investigating payments to Reform UK by a company controlled by the party's deputy leader, Richard Tice, BBC News has learned.
Britain Means Business gave the party two donations of £250,000 in the run-up to the 2024 general election, when Tice was party chairman.
Tice has said the money was given to his firm by Fiona Cottrell, a significant donor to Reform UK and mother of a convicted fraudster with close links to Nigel Farage.
Tice said: "This is the first I have heard of it - if true why are the Met Police briefing the BBC before contacting interested parties? Is the Met leadership now engaged in the widespread politically motivated smear campaign against Reform and its leaders?"
Earlier this month, the Times newspaper revealed that two donations given directly by Fiona Cottrell to Reform UK in May 2024 were being investigated by the Metropolitan Police.
That investigation relates to legislation governing elections, which bans concealing or disguising donations derived from an "impermissible" donor, or the use of "false" information about a donation including the amount or the identity of the donor.
The BBC has asked Fiona Cottrell for comment.
'Stringent vetting'
Britain Means Business, which is solely owned and controlled by Tice, received £1m from Fiona Cottrell in June 2024.
Disclosures to the Electoral Commission show that the company then donated a total of £500,000 to Reform UK in the same month.
Tice told the BBC earlier this month that it was entirely his choice for the company to give half of the money from Fiona Cottrell to his party.
The payments came to light when the Guardian newspaper revealed they had been flagged to the National Crime Agency as part of its Suspicious Activity Reports programme.
Now BBC News has learned that they are part of the Met's investigation into donations to Reform UK.
The BBC understands that the party was not aware of the investigation into the payments from Britain Means Business.
A Reform UK spokesman said: "Reform takes pride in its stringent vetting of donations and always ensures that the Electoral Commission guidelines on donations, as set out in the Political Parties, Elections and Referendums Act 2000, are strictly followed, as has been the case with donations so far."
'Frozen' account
All four payments were made in the weeks before the general election on 4 July 2024, when Farage and Tice were first elected to Parliament:
The first direct donation from Ms Cottrell of £250,000 appeared in the party's accounts on 9 May
The second, also £250,000, appeared a few weeks later on 29 May, just over a month before polling day
One payment from Britain Means Business of £250,000 was made on 10 June
Another payment from Britain Means Business of £250,000 was made on 12 June.
Tice was chairman of Reform UK until July 11, having previously been its leader. He then became deputy leader.
Records of all the donations have been published by the Electoral Commission.
Records on the Commission's website show Reform's bank account was frozen in the weeks before the election.
Other notes on the site suggest the account was first frozen a maximum of nine days after Britain Means Business's second donation.
-BBC
Britain Means Business gave the party two donations of £250,000 in the run-up to the 2024 general election, when Tice was party chairman.
Tice has said the money was given to his firm by Fiona Cottrell, a significant donor to Reform UK and mother of a convicted fraudster with close links to Nigel Farage.
Tice said: "This is the first I have heard of it - if true why are the Met Police briefing the BBC before contacting interested parties? Is the Met leadership now engaged in the widespread politically motivated smear campaign against Reform and its leaders?"
Earlier this month, the Times newspaper revealed that two donations given directly by Fiona Cottrell to Reform UK in May 2024 were being investigated by the Metropolitan Police.
That investigation relates to legislation governing elections, which bans concealing or disguising donations derived from an "impermissible" donor, or the use of "false" information about a donation including the amount or the identity of the donor.
The BBC has asked Fiona Cottrell for comment.
'Stringent vetting'
Britain Means Business, which is solely owned and controlled by Tice, received £1m from Fiona Cottrell in June 2024.
Disclosures to the Electoral Commission show that the company then donated a total of £500,000 to Reform UK in the same month.
Tice told the BBC earlier this month that it was entirely his choice for the company to give half of the money from Fiona Cottrell to his party.
The payments came to light when the Guardian newspaper revealed they had been flagged to the National Crime Agency as part of its Suspicious Activity Reports programme.
Now BBC News has learned that they are part of the Met's investigation into donations to Reform UK.
The BBC understands that the party was not aware of the investigation into the payments from Britain Means Business.
A Reform UK spokesman said: "Reform takes pride in its stringent vetting of donations and always ensures that the Electoral Commission guidelines on donations, as set out in the Political Parties, Elections and Referendums Act 2000, are strictly followed, as has been the case with donations so far."
'Frozen' account
All four payments were made in the weeks before the general election on 4 July 2024, when Farage and Tice were first elected to Parliament:
The first direct donation from Ms Cottrell of £250,000 appeared in the party's accounts on 9 May
The second, also £250,000, appeared a few weeks later on 29 May, just over a month before polling day
One payment from Britain Means Business of £250,000 was made on 10 June
Another payment from Britain Means Business of £250,000 was made on 12 June.
Tice was chairman of Reform UK until July 11, having previously been its leader. He then became deputy leader.
Records of all the donations have been published by the Electoral Commission.
Records on the Commission's website show Reform's bank account was frozen in the weeks before the election.
Other notes on the site suggest the account was first frozen a maximum of nine days after Britain Means Business's second donation.
-BBC
