A FORMER Scottish Tory candidate linked to a "dark money" donation in the Brexit referendum is facing fresh questions about his ties to the Democratic Unionist Party in Northern Ireland.

The secretive Constitutional Research Council, chaired by Clarkston-based Richard Cook, gave the DUP over £425,000 ahead of the EU vote, but it does not have to say where the money came from.

It has now emerged that Cook attended a DUP champagne networking reception, as well as an “Ulster Fry” breakfast event, at the Tory conference in Birmingham after the Brexit result.

Cook’s lawyer declined to answer questions on whether his client or the CRC helped organise or fund the reception.

However, his presence at the events has fuelled calls for him to reveal the CRC funders.

SNP MP Pete Wishart said: “As if they weren't in enough hot water already, these fresh revelations raise further questions about Richard Cook and the shadowy CRC.

“These breakfasts and champagne receptions that he schmoozed around at emphasise the need for him to come clean and explain where the CRC got its money from for the £425,000 donation.”

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The pro-Brexit DUP, which also keeps the Tories in power at Westminster, confirmed last year that it had received over £425,000 from the little-known organisation during the EU campaign.

However, although the huge sum was given to the DUP, much of the cash was spent by the party on a high-profile wraparound ad in the Metro newspaper, which is not sold in Northern Ireland.

The DUP did not have to declare the CRC as the source – donations at that point were kept secret for security reasons – and only did so voluntarily.

The revelation resulted in a huge amount of scrutiny of the CRC, which is not a company and has no website, published accounts or social media presence.

Cook, a former vice-chair of the Scottish Tories, is the only figure linked to the body. He has consistently declined to name the individuals who fund the CRC.

Critics have argued that it is unhealthy for one group to be able to donate such a huge sum without having to declare where the money has came from. The body has been subject to extensive reporting by the BBC and Channel 4.

Although the scrutiny of the CRC has centred on the Brexit donation, the Sunday Herald can reveal that Cook maintained his links to the DUP after the result.

At the Tory conference in October 2016, DUP leader Arlene Foster was the star turn at the “Ulster Fry” event attended by other political heavyweights from Northern Ireland.

The conference took place weeks after Theresa May had replaced David Cameron as Prime Minister and when Foster was First Minister of Northern Ireland. The DUP explicitly pitched themselves as a party that could help the Tories on Brexit.

Footage of the event shows Cook sitting yards from James Brokenshire, at that point Theresa May’s Secretary of State for Northern Ireland, while listening to Foster.

Hours later, at an art gallery in the city’s International Conference Centre, the DUP hosted a “making Brexit work” champagne reception.

An ITV broadcast showed Cook near the entrance while another picture revealed the former Tory candidate standing close to the queue of people waiting to enter.

The Ulster Fry event (image from ITV footage)

The queue at the DUP champagne reception. #CPC16 pic.twitter.com/dUE5qioDm5 — Stephen Walker (@StepWalkTV) 4 October 2016

Image: Cook is at the bottom left of the photograph, wearing a tie

A conference source said Cook attended the reception and was by the side of senior DUP figures. The insider said it looked like Cook may have been part of the DUP delegation.

The event caused controversy as the socially conservative DUP was founded by teetotaller Dr Ian Paisley, who famously referred to alcohol as the “devil’s buttermilk”.

The DUP confirmed receiving this newspaper’s question on whether Cook or the CRC had either organised or funded the reception, but offered no response.

Labour MSP Neil Findlay said: "This is yet another revelation in the troubling saga of the 'dark money' being fed into the Conservatives and their bedfellows the DUP in recent years.

"The public have a right to know who is bankrolling these two governing parties and what do these secretive donors expect in return for their large sums of money.”

Cook made several unsuccessful attempts at getting elected for the Scottish Tories, such as when he stood in Glasgow Cathcart in 2001 and polled 13.4 per cent.

He was his party’s candidate in the Holyrood by-election in the same seat four years later, but again came third.

Cook’s most high profile election bid was in 2010 when he tried to unseat Labour’s Jim Murphy in East Renfrewshire. The right-winger lost by over 10,000 votes, after which he departed the political stage in Scotland and focused on his business interests.

Speaking to this newspaper last year, Cook said the CRC is regulated by the Electoral Commission, operates solely in the UK and accepts donations only from eligible UK donors.

He declined to name any of the CRC contributors, but said that Scots had donated to the Council.

The CRC also donated £6,500 to MP and Tory Brexiteer Steve Baker, who quit May’s Cabinet recently in protest over her strategy for leaving the EU.