LONDON (AP) — The former head of the official "Leave" campaign in Britain's 2016 vote on European Union membership is denying breaking spending rules ahead of a report from the country's electoral watchdog.

The Electoral Commission has not yet published its report on Vote Leave.

But Matthew Elliott, who headed the group, says the commission has concluded that Vote Leave broke rules by donating more than 600,000 pounds ($800,000) to another group then using the money for its own activities.

Elliott denied wrongdoing Wednesday, saying Vote Leave acted "both within the letter of the law and also the spirit."

The Electoral Commission has conducted several investigations into the referendum, which was won by those wanting Britain to leave the EU.

Another pro-Brexit organization, Leave.EU, was fined 70,000 pounds in May for overspending and filing inaccurate records.