RUTH Davidson is facing mounting calls to quit as an MSP over her £50,000 second job with a PR firm as it emerged she has also set up her own consultancy business.

The former Scottish Conservative leader was accused of holding her constituents and the Scottish Parliament “in contempt” after she accepted a position with Tulchan Communications, where she will work just 24 days a year.

The Herald can also reveal Ms Davidson set up a management consultancy called Kirkholm Broadlands Ltd with her partner Jen Wilson 11 days ago, but did not mention it when she announced her work with Tulchan.

Camley's Cartoon: Two jobs for Ruth Davidson.

Documents lodged with Companies House show the firm was incorporated on October 14 with Ms Davidson and Ms Wilson both registered as directors and shareholders.

A Scottish Tory spokesman said Ms Davidson had set up the business “as a way of separating this work from politics, as many other politicians do”, and insisted it had no impact on her commitment to stay on as an MSP.

READ MORE: 'Conflict of interest' row over Ruth Davidson's PR role

He said it was connected to her job at Tulchan, but was also "there as a facility for her to do consultancy in the future too, even if that’s years down the line".

Limited companies can be more tax efficient than being paid a direct salary.

Referring to her new PR role, the spokesman said: “Ruth’s business advisory role is well within all parliamentary and industry rules.

“It is far less onerous than the party leadership she held for eight years, and she is able to complete the 16 hours a month it requires while still having more time for her family and constituency. Ruth is committed to seeing out her term as the MSP for Edinburgh Central.”

But Labour MSP Neil Findlay accused Ms Davidson – who was recently appointed to the Scottish Parliament’s corporate body, which oversees its workings – of bringing Holyrood into disrepute.

He said: “If she wants to continue pocketing tens of thousands of pounds from this lobbying firm she should resign as an MSP.

“The people of Edinburgh deserve an MSP that will represent them, not private corporations.”

Mr Findlay, who is putting forward legislation to stop MSPs taking second jobs, has lodged a motion at Holyrood calling on Ms Davidson to step down from the corporate body and “consider her position”.

He said news of Ms Davidson's consultancy business "goes straight to the heart of what is an unsavoury feature of the political system", with politicians appearing to use their positions to make money.

READ MORE: Ruth Davidson urged to resign as an MSP after accepting £50k PR job

Scottish Green MSP Alison Johnstone said: “The people of Edinburgh Central elected Ruth Davidson to represent them, not use her position to earn £50,000 from lobbyists.

“This is clearly a conflict of interest. Davidson needs to resign from the corporate body and as an MSP so Edinburgh Central can elect a committed representative.

“Most folk who take second jobs do so through pressing necessity. It’s time for a by-election in Edinburgh Central, not to mention a change in the law.

“Neil Findlay’s bill on second jobs for MSPs should be fast tracked to stop this happening again.”

SNP MSP Gordon MacDonald said: “This is a monumental misjudgement from Ruth Davidson, who simply cannot be allowed to accept cash from a lobbying firm while continuing to sit as an MSP.

“That’s not only a conflict of interest – it’s holding her constituents, and the Scottish Parliament as a whole, in contempt.

“Ruth Davidson needs to decide which day job matters. If she isn’t interested in focusing on her role as an MSP she should allow the people of Edinburgh Central to pick a representative who is.

“If she is brazen enough to continue sitting as an MSP, then the questions and pressure on her will simply continue to pile up.”

Scottish Liberal Democrat MSP Mike Rumbles also joined calls for Ms Davidson to step down.

He said: “Collecting almost twice what the average Scot earns in a year for a handful of days’ work, on top of her MSPs salary is an absolute joke.

“It spells the end for the growth of the Scottish Conservatives now their former leader is walking away for a fat cat job in the City of London.

"Ruth Davidson has let the people of Edinburgh Central down. If she's not willing to give them proper representation she should step aside and let them choose a new MSP."

Tulchan, which has offices in London and Singapore, is a strategic financial and corporate communications advisory firm.

Its website says Ms Davidson, who already earns £63,579 as an MSP, will advise clients on “changing political demands and providing stakeholder value”.

She told the Evening Standard she would not be lobbying or talking to ministers. Tulchan has also stressed this.

However, the Public Relations and Communications Association (PRCA), the world’s largest PR trade body, criticised the move as unethical.

Director general Francis Ingham said: “It is simply wrong for lobbying agencies to employ legislators.

“The possible conflict of interest in doing so is clear, and damages the reputation of both our industry, and of the political process.”

It comes after last week’s announcement that Ms Davidson, a former BBC journalist, is to chair ITV’s new Mental Health Advisory Group, created following the deaths of participants of the Jeremy Kyle Show and Love Island.

Andrew Feldman, managing partner at Tulchan Communications and a Tory peer, said he was “delighted” by Ms Davidson’s appointment, adding: “I have no doubt that our clients will benefit immensely from her insight and unique perspective on the rapidly developing evolving relationship between business and politics and the need to navigate the shifting demands of a broader range of stakeholders.”

Ms Davidson quit as Scottish Tory leader in August, citing both "professional and personal" reasons.

She had a baby last year, but was also seen as a strong critic of Boris Johnson's Brexit strategy.