The SNP unveiled its youth policies

Labour geared up for the 1 May election by launching its campaign bus.

The party's leader Jack McConnell then returned to Lanarkshire, where he hopes to retain the Motherwell and Wishaw constituency seat in parliament.

Lib Dem leader Jim Wallace was campaigning at home in Orkney but the party's social justice spokesman Robert Brown outlined plans to promote energy efficiency.

Ballot box

He unveiled plans to boost the use of solar roof panels by changing building regulations to ensure renewable energy systems are installed in new public-funded premises.

By using more solar panels householders, schools, hospitals and other public bodies could save on bills as well as limiting their impact on the environment, he said.

Scottish National Party leader John Swinney urged young people in Scotland to head to the ballot box in the forthcoming Holyrood elections.

Campaigning in Dundee, Mr Swinney said they should not miss their opportunity to have a say on issues such as tuition fees.

He pledged to abolish graduate endowment payments for university students and to reduce the voting age to 16.

David McLetchie was campaigning in his constituency

He said: "Labour introduced tuition fees, the Lib Dems sustained them, breaking their promise to Scotland's students, and the Tories want top-up fees.

"The SNP is the only party that can be trusted to abolish tuition fees once and for all."

Tory candidates were concentrating on getting their message across to Scots as shoppers and day-trippers came out in numbers over the weekend.

Formal period

Meanwhile, a new opinion poll has suggested that the SNP has taken a narrow lead over Labour in the leadership race for the Holyrood elections

The NFO System Three survey for the Herald puts the Nationalists level with Labour in the first vote for the Scottish Parliament, and three points ahead in the second.

It is the first time in 30 years of polls that the SNP has gone level or ahead of Labour in a formal period of campaigning

On the first Holyrood vote, the Nationalists and Labour have 31% each, but in the second it is 29% to 26% in favour of the SNP.

Perform strongly

The Scottish Socialist Party has dropped two points in a month to 8% in second voting.

The party is now just a point behind the Scottish Tories.

A further point behind, on 7%, are the Greens, who are fighting only list seats.

However, the Liberal Democrats have continued to perform strongly, with a rise of two points in first voting to 16%, and three points to 18% in second voting.