ROBBIE DINWOODIE, TORCUIL CRICHTON and CHRIS WATT

Alex Salmond said today that there were no safe Labour seats in Scotland in the wake of the SNP's victory in Glasgow East.

Mr Salmond hailed a "sensational" by-election victory for his party, with Nationalist John Mason overturning a Labour majority of 13,507.

The results would not force Prime Minister Gordon Brown into calling a General Election, Mr Salmond said.

The First Minister, speaking at a press conference at a shopping centre in the constituency, insisted that voters in Glasgow East had sent a message to Mr Brown.

He said: "That message is 'change your policy or change your job'.

"I watched Conservative Party leader David Cameron this morning. All he could think about was an imminent General Election.

"I've got bad news for David - I don't think there's going to be an imminent General Election somehow.

"What we need for the people of the country is a change of policy. We can't allow the country to drift into recession.

"We need action - action against the rising prices which are hitting family budgets, action against the energy costs, action to inject more demands into the economy.

"That's the changes that are required and that's what the SNP will be using its political influence to secure."

The First Minister said the people of Glasgow East now had an "outstanding" MP in Mr Mason.

"We have now demonstrated that there are no safe seats for the Labour Party anywhere in Scotland," he said.

Yesterday's by-election had been a "test of strength" between the Labour Government at Westminster and his Holyrood administration.

"It was London Labour that was found wanting and the SNP in Scotland that emerged victorious," said the First Minister.

He pledged that the SNP would "march to the sound of the priorities of the people of Scotland".

He continued: "If we keep doing that then we're going to take some stopping come the General Election, the Scottish elections to come and the independence referendum in 2010."

Mr Mason said that, by electing him, "the people of Glasgow East have spoken for the whole of the country".

"We have sent a message to Gordon Brown. It's time for action, time for him to listen."

The new MP called on the Prime Minister to take action to reduce the price of fuel and the cost of energy.

When asked if he would like a General Election to be called, Mr Mason said: "I think I've been elected for a purpose.

"The first purpose was to send a message to Gordon Brown. We want the Government to change direction.

"It's not about a question of who is in the Government, it's about a better behaviour on the part of the Government towards the people.

"The personal challenge for me now is to work really hard for the next 18 months or whatever it is and build up a relationship with the people of the east end."

Mr Mason went on: "They've been missing that, I would have to say, with their MP for a number of years.

"That's a new thing and I would actually like 18 months to do that."

The SNP's stunning victory in Glasgow East will now to join the likes of Govan and Hamilton in reshaping modern Scottish history.

The result hugely surpassed the expectations of even the most optimistic of nationalists, as local councillor Mr Mason overturned a Labour majority of more than 13,500.

For the duration of the short campaign, following the resignation of Labour MP David Marshall, all sides had envisaged a close contest between the front runners.

And following a recount called by Labour with the margin so tight, the result was declared to triumphant Nationalist supporters at just after 2.20am.

Even going into yesterday's poll, Labour and SNP organisers put the contest on a knife edge, and until mid-evening last night, that was how the received wisdom remained. But at close of polling, as all activists converged on Tollcross Leisure Centre, in the heart of the constituency, it became clear that the earthquake predicted by Mr Salmond had begun to rumble.

Local Labour MPs and councillors began to admit that the result was going against them. While returns were still coming in, one east end politician told The Herald "It's just not working for us."

At around 12.40am, the Labour candidate Margaret Curran was welcomed into the hall by fellow politicians and her campaign team, and away from the media in a corner of the main hall, she appeared to make a tearful concession of defeat.

Shortly afterwards, SNP candidate Mr Mason entered the hall to the rapturous applause of his party activists, who were by then aware that history was in the making.

In the area of the hall reserved for the count's party observers, there was little sympathy for Labour. Tory Party officials claimed that Mr Brown had received the bloody nose he had coming, while representatives of minor parties, such as the Socialists and Greens, were also pleased that Labour had lost its stranglehold on the east end of Glasgow.

Senior Labour politicians at the count had begun to admit earlier in the evening that their party now needed a whole new approach to its relationship with its former heartlands.

"We now know things have got badly out of touch," said one. "The SNP won in the aspirational areas, and we have to learn that lesson."

There was also the whole question about what the impact of such a cutting defeat would be on Mr Brown's leadership.

Speaking of his win last night, Mr Mason said: "This is a victory of epic proportions, and off the Richter Scale," adding that this was the first by-election in British history that represented a contest between two governments.

The SNP pointed out that the 24% swing came close to the shift required to take every Labour seat in Scotland.

Deputy SNP leader Nicola Sturgeon, speaking on BBC TV, said: "We're seeing a movement to the SNP of truly epic proportions"

Steven Purcell, the Labour leader of Glasgow Council, said: "The biggest issue was about the economy, but there are wider issues that we in the Labour Party have to think about. When we won in 1997, we had a powerful way of delivering that message, but more important is what the message is, and we have to look at a much more radical approach to our policy agenda.

"In the early years of this government we were radical, and we need a debate about what the next decade is going to be about."

Jim Murphy, Labour MP for Eastwood and Europe minister, told STV: "It's a bad seat to lose, but I'm confident that we can win this back at the next general election."

"Governnment is always about the future. We're talking about a fourth term. There isn't a sense of gratitude from people. It's about what you're going to do next."