Scotland Yard are looking into claims that Labour banned fox hunting in return for a £1million donation to the party.
The new allegations reveal that the 2004 ban was suggested in return for a large donation from the animal rights group, the International Fund for Animal Welfare (IFAW).
Lord Mandelson and another senior Labour figure are alleged to have been behind the move.
The disgraced former US ambassadors’ accounts have been central to a formal complaint made by pro-hunting campaigners requesting that the Metropolitan Police investigate the party for alleged misconduct in public office.
A spokesman from the force said: “On Monday, April 20 we received a report in relation to a donation made to a political party prior to the 1997 general election.
“Officers are currently assessing this report.”
Police sources added that it would be “inaccurate at this stage” to suggest that the Met had started an investigation or that any individual was under investigation, the Telegraph reports.
It added: “It will initially go through the first line of assessment to make sure everything is recorded properly. At this point it will then be passed to the relevant unit for investigation.”

It mimics a traditional hunt, with hounds following an animal scent laid and hunters trailing the pack on horseback.
