As a result it is expected that she will now seek to bring about a dramatic change in the government’s negotiating position which hitherto has been opposed to both the single market and the customs union. At a press conference in Edinburgh Ms Davidson said: “We must seek to deliver an open Brexit, not a closed one, which puts out country’s economic growth first.” In answer to questions she said she wanted the “greatest possible amount of free trade”. In a humiliating setback for Ms Sturgeon, the SNP won only 37 per cent of the popular vote and lost the support of half a million Scots compared to the 2015 election.It appeared the Conservatives had pulled off the biggest shock by ousting Mr Robertson, Ms Sturgeon’s deputy and the SNP’s Westminster leader, in Moray. However, this was eclipsed when they defeated Mr Salmond in Gordon, a result that stunned the Nationalists.Labour also won a series of unexpected gains, including Glasgow North East, as the surge in support for Jeremy Corbyn spread north of the border. Ms Sturgeon said this partly explained the SNP slump, with Left-wing and pro-independence voters switching to Labour.Speaking at her Bute House residence in Edinburgh about her referendum demand, Ms Sturgeon said: “We will reflect on these results, we will listen to voters and we will consider very carefully the best way forward for Scotland, a way forward that is in the interests of all Scotland.“I will take the opportunity of saying more on that front in the days to come.”But Ms Davidson said the election in Scotland “was dominated by one issue” and SNP MPs who lost their seats had “paid the price” for Ms Sturgeon’s failed referendum gamble. Fresh from her success in winning an extra 12 Scottish seats in Thursday’s election, at the same time as the Prime Minister was losing 21 constituencies in England, Ms Davidson also vowed to use her Commons votes to prioritise the single market over curbing immigration.This is certain to split Tory ranks as Mrs May has pledged to take the UK out of both the single market and the EU customs union as part of her Brexit negotiations, which begin next week. Most Scots voted Remain in the EU referendum and Ms Davidson has repeatedly said that she favours Britain reaching an agreement that allows it to stay in both the single market and customs union. But after notching up the biggest Tory victory in Scotland in nearly 40 years, the Scottish party leader said that the election result did not give the Prime Minister a mandate to take Britain out of the single market. Although she has previously said she does not mind if this is achieved by Mrs May’s plan for a free trade deal, she has also argued that the UK should keep free movement if that is price of maintaining open access to European markets.Speaking at a press conference at her Bute House residence in Edinburgh, Ms Sturgeon said SNP MPs would also try and use their influence in a hung parliament to stop a hard Brexit.The First Minister was forced to admit a massive backlash against her referendum demand was “undoubtedly” a factor in her party losing 21 MPs, including Mr Salmond and Angus Robertson, and pledged to “consider very carefully” her next steps over the coming days.But Ms Davidson, who led the Scottish Tories to their best result since 1983, said that was “not enough” and demanded Ms Sturgeon immediately dump a plan she said had turned out to be “a massive political miscalculation.” “What people do expect is that, right now, the SNP gives Scotland a break. Simply put, Scotland has had its fill,” the Scottish Tory leader said. Ms Davidson also signalled her opposition to Mrs May’s deal with the DUP in blunt fashion by tweeting a link to the same-sex marriage lecture she gave at Amnesty ‘s Pride lecture in Belfast last year.She is engaged to Jen Wilson, an Irish Catholic Christian who campaigned during the Republic’s same-sex marriage referendum, is a practising Christian herself and has said she would like to get married in a local church.Her views could not be further from those of the DUP, a staunch opponent of same-sex marriage and supporter of the “traditional” definition of marriage. Last night, Ms Davidson said she had sought and received assurances from the Prime Minister that she would try to advance gay rights in Northern Ireland despite the DUP’s record.Ms Davidson flexed her political muscle following a disastrous night for the SNP, which saw Alex Salmond lose his seat. Nicola Sturgeon hinted that she will row back on her plan for a second independence referendum but Ms Davidson demanded she “give Scotland a break” by immediately taking the plan off the table.The Nationalists ended up with 35 seats, the Tories 13, Labour seven and the Liberal Democrats four. But this compares with the 56 seats the Nationalists won in 2015, when the other three parties held on to only one constituency each. Ruth Davidson is to defy Theresa May’s plans for a hard Brexit and tear her Scottish party away from English control after the UK Tories’ disastrous General Election result.Amid a growing clamour among senior Tories in London for Ms Davidson to be given a top position in the UK party, her aides are working on a deal that would see the Scottish party break away to form a separate organisation. She is reported to have been continually second guessing decisions made in Edinburgh. This came to a head recently when Ms Davidson was “ordered” not to run a distinctive Scottish campaign but instead to “stick to the script” devised in London of pinning the entire Tory effort around Mrs May and Brexit.This ran completely contrary to the issue Ms Davidson favoured – namely the SNP demanding another independence referendum. Ms Davidson was determined to oppose this demand and reckoned her opposition chimed with the vast majority of Scottish voters.As a result she ignored the London “orders”, with the result that her campaign saw a gain of 12 seats, while in England Mrs May saw a loss of the same number.Given the lack of an overall majority, the Scottish Tory votes would be crucial to Prime Minister May getting her legislation through the Commons. Above all their votes could make or break her Brexit negotiations. However, the Conservatives in Scotland have complained of too much “interference” from London, since Mrs May assumed office last year. The focus of their annoyance appears to be Scottish-born Fiona Hill, the Downing Street communications chief. It would maintain a close relationship with the English party – they have been joined together as part of the United Kingdom Conservative and Unionist Party since 1965 – and its 13 MPs would take the Tory whip at the Commons.Although it has been mooted for some time, the imminent split between the Scottish and English parties is a direct result of a dramatic deterioration in relations between the Scottish Tory hierarchy in Edinburgh and 10 Downing Street. Ruth Davidson speaks at a post-election press conferenceCredit:Getty Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.