The officially designated Brexit campaign 'cheated' during the European Union referendum, a whistleblower has claimed.

The claims centre around Vote Leave's links to another campaign - BeLeave - which it helped fund.

Shahmir Sanni, who worked on the campaign, claimed Vote Leave used it to get around strict spending limits set by the Electoral Commission.

Shahmir Sanni, left, has accused Theresa May's political adviser Stephen Parkinson, right, of 'outing' him because he was afraid Mr Sanni was going to blow the whistle about Vote Leave's conduct during the EU referendum. Mr Parkinson released a statement which said he was involved in a relationship with Mr Sanni for 18 months

Vote Leave has strongly denied wrongdoing and said the £625,000 donated to BeLeave was within the rules.

But Mr Sanni told Channel 4 News: 'I know that Vote Leave cheated ... I know that people have been lied to and that the referendum wasn't legitimate.'

Mr Sanni was in a relationship with senior Vote Leave figure Stephen Parkinson - now Theresa May's political secretary - at the time of the referendum and claimed through his lawyers he was 'outed' by the Number 10 aide in the run-up to the Channel 4 disclosure.

Mr Sanni went to the Electoral Commission with two other pro-Brexit friends on Thursday, who say they helped the Vote Leave campaign two years ago, Channel 4 reported.

Their lawyers have given the election watchdog signed statements.

Mr Sanni told the broadcaster he was initially a Vote Leave outreach volunteer but he was then assigned to BeLeave.

Vote Leave said it did not recall Mr Sanni working as a volunteer, but he was 'like hundreds of others who occasionally visited the offices'.

Mr Sanni said that he and BeLeave's co-founder Darren Grimes always reported to Mr Parkinson.

Mr Sanni claimed he was initially a Vote Leave 'outreach volunteer' before he was assigned to the BeLeave campaign. He said BeLeave's co-founder Darren Grimes 'always' reported to his former boyfriend Stephen Parkinson. He added: 'There was no time where anything BeLeave did didn't go through Stephen'

'There was no time where anything BeLeave did didn't go through Stephen,' he said.

In the final 10 days of the 2016 referendum campaign Vote Leave donated £625,000 to Mr Grimes, who was registered as a permitted participant, with the money used to pay Canadian data firm Aggregate IQ (AIQ), the programme said.

Asked whether they could have refused to spend the money on AIQ, Mr Sanni said: 'We didn't ever feel like we had that level of control.

'That's what I mean, we never felt like we had control over the organisation itself.'

He claimed: 'In effect they used BeLeave to over-spend, and not just by a small amount ... Almost two-thirds of a million pounds makes all the difference and it wasn't legal.'

Mr Sanni released a statement tonight through his solicitor's Bindmans

Mr Parkinson said he was 'saddened' by the 'factually incorrect and misleading' statements by Mr Sanni and his lawyers.

He added: 'At the relevant time during the referendum period, the commission advised Vote Leave that it was permissible to make a donation in the way it proposed to do to BeLeave.

'Twice since the referendum the commission has investigated this matter, and twice it has found no evidence of wrongdoing. A third investigation into the same issue is currently taking place.

'The Electoral Commission has not contacted me in relation to any of these inquiries, but I will of course be happy to assist in them if they wish me to do so.

'I firmly deny the allegations in the programme.

'I had no responsibility for digital campaigning or donations on the Vote Leave campaign, and am confident that I stayed within the law and strict spending rules at all times.'

Mr Grimes also denies all the allegations, Channel 4 said.

A Vote Leave spokesman said it had 'twice been cleared on this matter by the Electoral Commission' adding: 'There are now a number of new accusations and allegations.

'While many of them seem irrelevant or trivial, some are serious and potentially damaging to the reputations of those caught up in those allegations.

'As has been the case throughout, Vote Leave is obligated to review - to the extent it can after this long elapsed period since the referendum - all such allegations, and is doing so.

'We will as appropriate share any relevant findings with the Electoral Commission, again as we have always done.'

An Electoral Commission spokeswoman said: 'The commission has a number of investigations open in relation to campaigners at the EU Referendum; it does not comment on live investigations. '

Mr Sanni was forced to reveal his sexuality to his mother and members of his family in Pakistan following the statement.

It came after Mr Sanni was said to be set to come forward to allege the Vote Leave campaign, who he worked for, broke campaign finance laws by donating money to another pro-Brexit group, BeLeave, and co-ordinating how it was spent.

In a statement revealing their relationship, Mr Parkinson admitted he had spoken to Mr Sanni about the two campaigns, but denied wrongdoing.

He said he gave him 'advice and encouragement' but said he was 'confident' Vote Leave acted within the law.

Vote Leave donated £625,000 to BeLeave, a campaign aimed at the youth vote.

Electoral law forbids Vote Leave having any say in how the cash is spent.

Vote Leave would have been unable to spend the money itself because it was approaching the £7million campaign spending limit.

Responding to the sudden 'outing', Mr Sanni was released a statement through is solicitors Bindmans.

'I represent Shahmir Sanni, who has provided information to the media as a whistleblower about matters relating to the conduct of the Vote Leave campaign during the EU Referendum.

'10 Downing Street tonight confirmed an official statement to the media on behalf of Stephen Parkinson, Political Secretary to the Prime Minister, disclosing my client's sexuality publicly.

'We believe this is the first time a Downing Street official statement has been used to out someone. My client is now having to come out to his mother and family tonight, and members of his family in Pakistan are being forced to take urgent protective measures to ensure their safety.'

Mr Sanni added: 'It's sad that Stephen feels he can't tell the truth about cheating in the Referendum.

'I think he understands why I had to do the right thing and let people know what really happened.

'But I never imagined that he, with the help of Number 10, would choose to tell the world I am gay, in a last desperate attempt to scare me.

'This is something I've never told most of my friends or family, here or in Pakistan, some of whom are having to take measures to ensure their safety.

'He knew the danger it would cause, and that's why he did it.

'My coming out should have happened at a moment of my choosing - not his or the Government's.

'Some things are more important than politics and I hope that one day he agrees.'

In an earlier statement, according to the Times Mr Parkinson wrote: 'Shahmir became an occasional volunteer for Vote Leave and other Leave campaigns, and we began a personal relationship.

'We subsequently dated for 18 months, splitting up — I thought amicably — in September 2017. That is the capacity in which I gave Shahmir advice and encouragement, and I can understand if the lines became blurred for him, but I am clear that I did not direct the activities of any separate campaign groups.

'I had no responsibility for digital campaigning or donations during the referendum, and am confident that Vote Leave acted entirely within the law and strict spending rules at all times.'

Number 10 this morning told MailOnline: 'This is a political matter for CCHQ (Conservative Campaign Head Quarters).

MailOnline has approached CCHQ for a comment.