Theresa May will vow never to allow the UK to become "looser and weaker'' in a speech ahead of a meeting in Scotland with Nicola Sturgeon.
Today On The Campaign Trail
Nicola Sturgeon has welcomed the Scottish Sun's endorsement of the SNP in next week's General Election as "another boost'' for her party's campaign.
But the Scottish First Minister insisted the support which really matters is that of the voters around the country for the SNP's "aspirational'' campaign.
The tabloid newspaper north of the border said the SNP will "fight harder for Scotland's interests at Westminster'' as it announced its backing for the party in the May 7 poll.
In a front page along a Star Wars theme, the headline reads "Stur Wars'' and Nicola Sturgeon is portrayed as Princess Leia.
Asked whether she was pleased to be portrayed as the Princess, Ms Sturgeon said: "I think I'll carry on being leader of SNP and campaign hard.
"I welcome the endorsement of the (Scottish) Sun. It's another boost for the SNP campaign, the first tabloid newspaper to support us in this election.
"But the support that really matters is the support of people right across Scotland and we'll be working hard every single day between now and next Thursday to say to people, if you want Scotland's voice to be heard, the only way to ensure that is to vote SNP and to send a big team of SNP MPs to stand up for Scotland and to stand up for better politics at Westminster, for the benefit of people right across the UK.''
The Scottish Sun's position emerged as the UK edition of The Sun announced it will support the Conservatives at the General Election.
One of the reasons it listed was to "stop SNP running the country''.
Ms Sturgeon responded to the development as she hit the campaign trail in the Leith area of Edinburgh and unveiled the SNP's final advert of the election campaign.
The picture, showing some of the green seats in the House of Commons turned into red tartan, proclaims: "More SNP seats. More power for Scotland.''
Ms Sturgeon, who was mobbed by supporters during the launch and posed for a number of photographs, said the message behind the campaign was straightforward.
She said: "The simple message that we'll take to every corner of the country over the next seven days is this one: If you want Scotland's voice to be louder, if you want the Westminster system to work better for people in Scotland and people across the UK then you've got to come out and vote SNP because the more seats we have in the House of Commons the more power Scotland has.''
Scottish Labour leader Jim Murphy said: "Sun readers down south are being told to go out and vote for the Tories and Sun readers in Scotland are being told to go out and vote for the SNP, either way you end up with the same thing - a Tory government.
"Only Labour is big enough, only Labour is strong enough to beat the Tories.
"Rupert Murdoch doesn't tell us how we vote. Rupert Murdoch is desperate for the Labour party to be defeated but I've got a greater confidence in the people of our country, north and south of the border, that Rupert Murdoch doesn't decide our elections any more.''
Mr Murphy launched a new campaign poster in Govan, Glasgow, where he was joined by his deputy Anas Sarwar and shadow Scottish secretary Margaret Curran.
The poster features a signpost with two directions - one suggesting a second independence referendum under the SNP and another pointing the way to a "fairer economy'' with Labour.
The candidate for East Renfrewshire said: "There's a week to go until the General Election and one third of all Scots is still undecided about how to vote
"So our appeal all across Scotland is, let's together build a fairer Scotland, let's abolish exploitative zero-hours contracts, let's have a higher minimum wage. Let's not go back to the divisions of last year where work places were split and families were divided.
"That's what will happen if these polls are repeated on election day and the SNP win all these seats, we're on the road to a second referendum with the SNP and that's not in Scotland's best interests.
"Most of Scotland, whether we voted yes or whether we voted no in the referendum, most of Scotland does not want to go back to that division of last year. Let's come together as a country, let's work to build our nation as the fairest on earth rather than going back to the old divisions.''
Mr Murphy said Labour has a "huge amount of energy and determination'' as the final week of campaigning approaches and is confident of turning the polls around.
On a campaign visit to Hopetoun Farm Shop near Edinburgh, Scottish Liberal Democrat leader Willie Rennie highlighted his party's plans to raise the personal income tax allowance to £12,500 by the end of the next parliament.
He criticised Ms Sturgeon for failing to rule out putting a commitment to hold another referendum on independence in the SNP manifesto for the Scottish Parliament election next year during First Minister's Questions at Holyrood.
Mr Rennie said: "While Lib Dems set out our plans to give Scots a further £400 tax cut, the SNP faces further chaos on their plans for a second referendum on independence.
"In each of our 11 held seats, the choice facing voters is clear. The Liberal Democrats will anchor the economy in the centre ground, increasing the personal allowance to £12,500 as part of a red line for any coalition negotiation.
"This builds on the tax cut Lib Dems have already delivered in coalition for millions of Scots.
"Our responsible, stable plans will build a stronger economy and a fairer society, stopping government from veering off left or right.
"The SNP wants to borrow even more than Labour whilst plunging Scotland into neverendum. People will be staggered that Nicola Sturgeon once again refused to set out when she plans to put forward a second referendum.
"If people want to stop the SNP from veering the country away from the economic centre ground, they must vote Lib Dem in each of our 11 held seats.''
Scottish Conservative leader Ruth Davidson launched her party's new party political broadcast in Edinburgh.
In the broadcast, she says: "I think when it comes to voting you should just vote for who you believe in.
"I believe in family and community. I believe in a strong economy so that we can pay down our debts and fund vital services like our NHS. And I believe in a strong Scotland rooted for good within our United Kingdom.
"So, for me, it's simple, and if you believe in these things too, then vote Scottish Conservatives.''
The broadcast features three voters who discuss why they are voting for the party on May 7.
One of the three, Dougie Thomson, a senior payroll administrator from Aberdeen, said: "I hope that what I say helps to resonate with voters that are more about the normal person than the politician and that it helps to connect more people to the cause.''
A Scottish boxer has died in Thailand of suspected heatstroke.
Scotland outperformed the rest of the UK last year with an annual increase of more than 15% in visitors to its attractions, new figures show.
The population of an iconic bird of prey is poised to soar after a scheme to boost golden eagle numbers attracted £1.3 million in funding.
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