The SNP is in crisis today after Nicola Sturgeon suspended her heir apparent from the party who quit as Finance Secretary in disgrace for bombarding a 16-year-old schoolboy with 'creepy' messages over six months.

Derek Mackay, 42, who was tipped to be the next First Minister of Scotland, contacted the boy out of the blue on Facebook and Instagram last summer, calling him 'really cute' before asking him to keep their exchanges secret.

But he resigned hours before presenting the SNP's Budget at Holyrood in Edinburgh today after the boy's mother published the 270 messages exchanged with her traumatised son and said she would go to the police.

Ms Sturgeon told the Scottish Parliament today his conduct 'falls seriously below the standard required of a minister' and revealed he had been suspended from both the party and the SNP parliamentary group at Holyrood 'pending further investigation'.

It is the second major blow to hit the SNP in the past year after former First Minister Alex Salmond resigned from the party 12 months ago to fight charges of sexually assaulting 10 women - and today's controversy involving another senior figure in Nicola Sturgeon's party could badly damage her demands for a second independence referendum after Brexit.

Salmond's trial, which starts on March 9, threatens to reveal more damaging information about the party and plunge Scottish Nationalists into more chaos.

Sturgeon is facing intense pressure from within her Remain-supporting party to secure the right to hold a second vote on breaking up the UK, as the latest poll shows 51 per cent of Scots would support leaving the union - the first time a majority has been recorded in favour since 2015.

But Boris Johnson is flatly refusing the demand raising the prospect of a potential legal battle between the SNP and the government.

In a humbling statement today Mr Mackay took 'full responsibility' for his 'foolish actions' and apologised 'unreservedly' to the boy and his family. And in a nod to the gravity of his resignation, which could hit the SNP's independence cause, he added: 'I am sorry to have let colleagues and supporters down'.

Mr Mackay, a father-of-two sons, came out as gay in 2013 when he left his wife of 12 years, Jennifer - the couple are separated but are not believed to be divorced and he lives with his physiotherapist boyfriend Fraser Adam in Bishopton near Glasgow.

Scottish finance Secretary Derek Mackay, 42, pictured left on his final photo call as a minister yesterday, and right with his estranged wife Jennifer in 2011, allegedly contacted the boy, 16, out of the blue on Facebook and Instagram - and has now quit because of his 'foolish actions'

A downbeat Nicola Sturgeon addressed Holyrood this afternoon (pictured) and announced Mackay, viewed as her heir apparent, was suspended from both the national and parliamentary party pending an investigation

These are text messages allegedly exchanged between Derek Mackay and a 16-year-old boy, who said he was distressed by the messages, forcing him to lie about his brother being injured to avoid meeting him

Mr Mackay quit as Finance Minister this morning - apologising to the boy and his family as well as the SNP and their supporters

SNP MSP set to be in charge of Scotland's £34bn budget is a 29-year-old who worked for two years as a trainee accountant A 29-year-old SNP starlet stepped in at the 11th hour to deliver Scotland's £34billion budget today after Nicola Sturgeon's Finance Secretary quit having been accused of using his position to 'groom' a 16-year-old boy. MSP Kate Forbes only found out that she would announce the Scottish Government's spending pledges for the coming year at around 8am today - just after Derek Mackay resigned in disgrace. Miss Forbes worked as a trainee accountant at Barclays for two years before entering politics full time in 2016, when she was elected in the Skye, Lochaber and Badenoch seat aged just 26. And Mackay's fall from grace this morning mean this afternoon the SNP's public finance minister became the first woman to deliver the Scottish Budget since devolution. Nicola Sturgeon patted the MSP on the back and cheered as she finished a speech where she blasted Brexit and held the top rate of income tax at 46 per cent - four per cent higher than the rest of the UK. Miss Forbes, a comprehensive schoolgirl from Dingwall born in 1990 who went on to study history at Cambridge, has already made history by becoming the first government minister who was born in the same decade that the parliament was created. Miss Forbes worked as a trainee accountant at Barclays for two years before entering politics full time. In 2016, aged 26, she won the Skye, Lochaber and Badenoch seat, increasing the SNP majority from 4,995 to 9,043. The fluent Gaelic speaker has been public finance and digital economy minister since 2018 but could now take Mackay's job as Finance Secretary. Advertisement

Addressing the Scottish Parliament this afternoon Nicola Sturgeon said: 'I do not condone his conduct in any way, shape or form. Derek has been suspended pending an investigation'. She added: 'If the family or the individual concerned wanted to speak to me, I would of course be happy to do that' but said she was 'unaware' of any other accusations about Mackay's conduct.

Police Scotland have said Derek Mackay has not been accused of any crime - but they are 'assessing information' after his messages with the child were published in the Scottish Sun this morning.

A spokesman said: 'We have not received any complaint of criminality, however we are currently assessing available information from media reporting and would encourage anyone with information to please come forward.

'Police Scotland will always listen to anyone who wishes to seek advice or formally report a matter to us.'

Scottish Tory leader Jackson Carlaw said today that his decision to resign as Finance Secretary isn't enough accusing Mr Mackay of attempting to 'groom' the teenager and saying he is no longer fit for office.

He said: 'We are all bewildered that Derek could have undertaken such a colossal lapse of judgement. I don't think she [Nicola Sturgeon] believes that simply accepting his resignation from Government is an end to the matter'

Scottish Labour leader Richard Leonard said: 'Derek Mackay's actions towards a schoolboy are beyond foolish, they are an abuse of power. They are nothing short of predatory, so this is serious'.

'I think there will be huge question to be asked, parents who will be concerned, and I think many colleagues in parliament who will wonder if Mr Mackay can continue to enjoy the confidence of his constituents or Parliament.

Scottish Liberal Democrat leader Willie Rennie said Mr Mackay should now step down as the MSP for Renfrewshire North and West. He told ITV Border: “It is really about the standards that we would expect from MSPs at this time and I think Derek Mackay has not behaved in the standard that we would expect from a member of the Scottish Parliament. I think it would be time for him to resign now'.

His resignation as a minister came exactly a week since Nicola Sturgeon goaded Boris Johnson over his refusal to grant a new referendum on Scottish independence, claiming he was scared of losing it.

The First Minister said that the Prime Minister's decision to block a new vote was 'a sign of weakness' as she continued to build her case the break up the UK.

The SNP leader used a speech in Edinburgh last Monday to encourage fellow nationalists not to waver in their support - but the new scandal is expected to damage the party and her cause.

Mr Mackay (right) lives with his boyfriend Fraser, pictured together in Fuerteventura over Christmas, after leaving his wife after coming to terms with his sexuality seven years ago

Nicola Sturgeon is besieged by the media after First Minister's Questions where she refused to comment further on Mackay's SNP future saying he is suspended pending an investigation

DEREK MACKAY'S POLITICAL CAREER AND HIS FALL FROM GRACE Childhood - Claims to have suffered abuse at the hands of his alcoholic father 1993 - Spent some time living with his mother in a homeless shelter in Renfrew with his brother when he was 13. 1 996 - Joins the SNP at age 16 1999 - Elected councillor for Renfrewshire at age 21 after graduating from Renfrew High School and abandoning his studies at the University of Paisley 2007 - Elected leader of Renfrewshire council 2011 - Elected as MSP and immediately appointed to the Cabinet 2014 - Appointed Minister for Transport by Nicola Sturgeon 2016 - Promoted to Finance Secretary February 6 2020 - Quits his job over claims he bombarded 16-year-old boy with messages Advertisement

Mr Mackay exchanged 270 messages for around six months before the teenager, who made it clear he was 16 more than once. In one message Mr Mackay allegedly asked him: 'And our chats are between us?' and when the boy agreed he then told him: 'Cool, then to be honest I think you are really cute.'

He had also invited the boy to a rugby event and told him he liked his haircut in messages published by The Scottish Sun. The teenager then avoided replying after telling the politician his mum would 'worry' after Mr Mackay invited him for dinner.

When the 'creepy' messages kept coming the schoolboy lied and told the MSP his brother had split his head open to avoid meeting him. Mr Mackay replied saying: 'Oh no, I hope he is okay' - but within three hours sent a new message asking: 'You not available now?'

When the 16-year-old started ignoring his messages the MSP sent a series of messages over a fortnight simply saying 'hey' or a waving emoji without getting a response - so then offered the boy rugby tickets.

Speaking today the teenager said: 'I just wanted to make something up because I didn't want to go. It was weird and even after I told him that he was still trying to get me to go. He asked if I was with my mum and dad.

'I just wanted to speak out to stop other people getting targeted like that. He's very high profile so it's worrying'.

The boy's mother, 37, has called for Nicola Sturgeon (with Mr Mackay in February last year) to sack the MSP for Renfrewshire North and West. She has now accepted his resignation and suspended him as she fights for a second independence referendum

Former Scottish first minister Alex Salmond leaving the High Court in Edinburgh on January 22 after appearing on a series of sexual assault and attempted rape charges. His trial will begin on March 9

Boris Johnson called Nicola Sturgeon 'that bloody Wee Jimmy Krankie woman' The Krankies, who Boris Johnson compared Nicola Sturgeon too, are a Scottish comedy duo who enjoyed success in the 1970s and 1980s Boris Johnson referred to Nicola Sturgeon as 'that bloody Wee Jimmy Krankie woman' in a foul-mouthed tirade during a Number 10 meeting to discuss this year's climate summit in Glasgow, it has been claimed. The UN summit, known as COP26, has become mired in controversy after David Cameron and William Hague both refused to host it in Scotland in November. And last week, ex-minister Claire O'Neill, previously president of the conference, was sacked by the PM's adviser Dominic Cummings. Now, it has emerged that Ms Perry O'Neill suggested the Prime Minister offer Ms Sturgeon a formal role to stop her Scottish National Party from damaging the event. However, it has been claimed the suggestion triggered a furious response from Mr Johnson, who allegedly said: 'Over my f****** dead body. I'm not being driven out of Scotland by that bloody Wee Jimmy Krankie woman.' Advertisement

The boy's mother, 37, had called for Nicola Sturgeon to sack the MSP for Renfrewshire North and West and told The Scottish Sun: 'A man like that is not supposed to say these sort of things to a boy.'

She claims the 42-year-old knew her son was 16 but continued to message him.

She has also said police should investigate her claims - although it is not clear what crime, if any, he could have committed.

The now outgoing finance secretary, who was bookies' favourite to succeed Sturgeon as Scottish First Minister, liked pictures of the youngster in sports gear and sent him messages on Christmas Day, according to The Sun.

The conversations between the pair are believed to have begun in August.

One saw Mr Mackay, who lives with his boyfriend in Bishopton, Renfrewshire, tell the boy about his sexuality, before deleting the post.

Spotting it before it disappeared, the boy said: 'As long as you're not trying anything I don't mind you being gay', to which Mr Mackay replied: 'Perfect'.

He tried to engage the youngster in politics, asking if he was in favour of Scottish independence, but the boy said he 'didn't have an opinion'.

Mr Mackay then offers to take the teenager to a Scottish Rugby Union event at Holyrood that took place in January.

It was this message that caught the attention of his mother, when he said he had been offered to go to a rugby reception by a politician.

Outraged, the boy's mother told The Sun: 'He should be made to apologise, not just to me but to everyone else who has been let down by this. I think he should be sacked to be honest.'

Hours later Mr Mackay quit and said in a statement: 'I take full responsibility for my actions. I have behaved foolishly and I am truly sorry.

'I apologise unreservedly to the individual involved and his family. I spoke last night with the First Minister and tendered my resignation with immediate effect.

'Serving in government has been a huge privilege and I am sorry to have let colleagues and supporters down.'

Mr Mackay had been due to unveil the Scottish Government's Budget for the next financial year today and it will now be presented by public finance minister Kate Forbes.

She claims the 42-year-old (pictured in April last year), who came out as gay in 2013 when he left his wife, knew her son was 16 but continued to message him. She has also said police should investigate her claims

Who is next in line to succeed Nicola Sturgeon as leader of the SNP now? Kate Forbes - 5/1 Twenty-nine-year-old Cambridge graduate Kate Forbes worked as an accountant before being elected as an MSP in 2016. She is currently minister for public finance and digital economy and will deliver the budget today in place of Derek MacKay John Swinney - 8/1 SNP veteran and current deputy first minister and leader of the party from 2000 to 2004. He is currently deputy first minister. He is on the softer wing of the party with regards to independence and resigned as leader after a series of poor election results. He is currently Deputy First Minister Angus Robertson - 10/ 1 Another SNP veteran who was an MP and leader of the party in the House of Commons from 2007 to 2017. A close ally of Alex Salmond. Advertisement

Accepting Mr Mackay's resignation, First Minister Nicola Sturgeon said: 'Derek has taken full responsibility for his actions and apologises unreservedly for them to the individual involved and to those he has let down. He has submitted his resignation as a government minister, which I have accepted.

'Derek has made a significant contribution to government, however he recognises that his behaviour has failed to meet the standards required.

'The minister for public finance, Kate Forbes, will present today's Scottish Government budget setting out our actions to support the economy, back our people and public services, and tackle the climate crisis, and that remains my government's focus.'

It is another blow for the SNP just a fortnight after former First Minister Alex Salmond appeared in court accused of sexually assaulting 10 women over a period of six years.

Mr Mackay hit headlines in February 2019 after former MP Jim Sheridan accused him of 'raping Scottish councils of cash' in a social media post about the Scottish budget.

Mr Sheridan, who is now a councillor in the area where Mr Mackay lives, was previously suspended over comments he made about the Jewish community. He was slammed by party members for using inappropriate language.

YouGov research published a week ago found 51 per cent of people in Scotland would support independence - the first time the firm has recorded a majority in favour since 2015 - but Boris Johnson is refusing to agree to one

Mr Mackay recently described splitting with his wife as he tried to 'wish away' his sexuality.

Can the SNP secure Indyref2 without the Boris Johnson's permission? The SNP is using Brexit to renew its calls for a second independence referendum. A majority of Scots voted to remain in the EU in the 2016 Brexit referendum and Nicola Sturgeon is using the UK's departure from bloc to demand a second vote on Scottish independence. The government in Westminster has to give the Scottish government permission to hold a second referendum - and Boris Johnson has point blank refused to do so. However Sturgeon could take her fight for another vote to the courts. She has not ruled out trying to hold a so-called 'consultative' second referendum - arguing that legal ambiguities empower the Scottish executive to hold a non-binding vote. Advertisement

He said previously: 'When I did fall in love with someone, who I met at university, I wanted it to work. And it did work. I've got two wonderful kids as a result of that genuine true love and marriage.

'It was only in later years that I thought, 'I think I need to fix this because clearly I'm gay. While this has been able to work, it's probably not right and won't last forever'. :

He added: 'Coming out? That probably ranks up there as the most difficult thing I've ever had to deal with.

'Because you think, 'What do I do? I've got a wife and kids'. I wanted to protect them from the impact.

'All of it was a worry – my career, my family, how people would treat me. The fear of the unknown.

'I'm sure you can appreciate that it wouldn't have been easy for my wife'.

Mr Mackay, who was first elected as a councillor aged 20, previously claimed he was 'saved' by the SNP after joining up aged 16 after being made homeless in 2013.

He told the pro-Scottish independence newspaper The National: 'I say it saved me, because I don't know where my life otherwise would have ended up. I was from a strong family, but one that was slightly chaotic, with a father who was an alcoholic and didn't treat us particularly well'.