Defiant Jim Murphy said he still believes he can be Scotland's first minister next year, despite leading Scottish Labour to its worst Westminster election result.

His party has been left with just one MP north of the border, losing 40 seats in a political earthquake which saw the SNP win 56 constituencies across the country, including the East Renfrewshire seat Mr Murphy had held since 1997.

Speaking just hours after defeat in his seat, Mr Murphy insisted he wants to stay on as Scottish Labour leader in a bid to address the problems his party faces.

Mr Murphy said Labour in Scotland had been "overwhelmed by history and by circumstance", as high-profile figures such as shadow foreign secretary Douglas Alexander and shadow Scottish secretary Margaret Curran fell to the SNP.

He said he stood for the leadership of the party in Scotland last year because, after the loss of two consecutive Holyrood elections and the "emotional hangover" from last year's referendum, the party faces "the biggest challenge in our 127-year history".

Mr Murphy insisted: "As leader I wanted to meet these challenges and I still do."

But already there have been calls for him to resign and, with the Scottish Labour leader now not holding elected office at either Holyrood or Westminster, questions will be asked about how long he can continue in the role.

Mr Murphy was elected to the post just five months ago, after his predecessor, Johann Lamont, quit, accusing the party in London of treating Scotland like a "branch office".

Asked if he still believes he could be first minister after next May's Scottish Parliament election, Mr Murphy said: "Yes."

He conceded the election had been "a dreadful night for our party", but said: "Far worse than that we are waking up on a terrible morning for Scotland and for working-class people across the UK as David Cameron prepares to form another government.

"The friends and colleagues that were defeated last night had been faithful servants to our party and forceful advocates for their constituents.

"But this isn't about them and it isn't about us. This isn't about individual careers, because, while we have lost seats, the thing that hurts most is the loss of hope faced with another five years of a government totally lacking in compassion, and totally lacking in vision."

mfl

Mr Murphy recalled that when he took on the job he said Labour "hadn't been good enough, we hadn't been radical enough, we hadn't reflected the optimism and self-confidence of modern Scotland".

He said those challenges still remain, adding while Labour had "worked every day to try to turn this round" in the General Election, the party found itself "overwhelmed by history and by circumstance".

Mr Murphy stated: "We make no excuses, a party can never blame the electorate, but we found ourselves hit by the perfect storm of three really significant factors.

"Firstly, the simple maths of a Yes vote finding a home in one party versus a No vote spread across three political parties. It is clear that it will be some time before the divisions of the referendum fade into distinction between traditional left and right wing politics in Scotland.

"Secondly, we were hit by two nationalisms, a Scottish nationalism reassuring people that they could vote SNP and get Labour, and an English nationalism, stoked up by David Cameron, warning 'vote for Labour and you will get the SNP'.

"Unsurprisingly, forced into an artificial contest between English nationalism and Scottish nationalism, many Scots, including many No voting Scots, chose the SNP.

"The third factor is of course the long standing problems that led me to stand for leadership of this remarkable party in the first place.

"We had for too long lacked a clear message, a clear offer, and a continuity of leadership - five leaders in just seven short years."

He added: "We didn't have the time nor space to turn that round in that short period.

"Some have said it was an impossible task to turn around all those years of gradual decline in five short months. But it hurts never the less."

With Nicola Sturgeon's SNP having sought to portray itself as the party of social justice in Scotland, Mr Murphy said Labour had "been beaten by a party who claimed our heritage, who clothed themselves in our values and copied many of our policies".

But he stressed: "With less than a year till the Scottish Parliament elections we cannot afford another period of introspection.

"People need us to be what we've always been when we're at our best, which is a voice for working people."

mfl

Asked if he would be resigning and if not why not, Mr Murphy said he and his deputy, Kezia Dugdale, had not had enough time to rebuild the party. He denied the result made his position untenable.

At a press conference in Glasgow, he insisted he wanted to be the leader of the fightback, adding: "Yes, this is a body blow ... and a real blow for our party, but we are determined to offer a period of stability, we are determined to help lead our party back.

"We know it has been a bloody awful night for the Scottish Labour Party and, more importantly, it's a dreadful result across the UK for working-class families who need a change."

Asked how much personal responsibility he felt for the near wipeout, Mr Murphy insisted that Labour "carries the can".

He added: "There is no shirking away from this ... there is a responsibility in good times and in bad times as a leader.

"Our determination is to rebuild from here, to rebuild with a continued sense of energy, with a continued sense of teamwork, thanking our activists."

Asked if the Labour constitution allowed him to stay on as leader despite losing his seat, Mr Murphy said the rules stipulate that a contender must be a parliamentarian at the time of the leadership contest.

He added: "The issue doesn't arise and I remain committed and will stand for the Scottish Parliament in 2016."

Asked how long it would take to rebuild the Labour Party, he said the process would be measured in outcomes rather than time.

He added: "There is no quick fix to the process of rebuilding ... there is no magic way to make this happen and it will take as long as it takes for us to re-earn the trust of the Scottish people.

"So that's not being measured by time, it's measured by outcomes."

Mr Murphy also insisted that the General Election result was "not a mandate for re-running the referendum argument".