NIGEL Farage will today insist Ukip is the only party that speaks to the whole of the United Kingdom and will provocatively brand the Tories, Labour and the SNP as mere regional parties.

The party leader's speech in Kent comes as the General Election campaign heats up with less than three months to go and with other keynote speeches today from David Cameron and Nick Clegg.

In a headline address in Kent, Mr Farage will speak about how Britain needs belief in itself, its peoples, institutions and its future.

He will claim Ukip, as the only party with elected representatives in the four parts of the UK, is the only one which talks to the whole nation.

The others, he will argue, are "regional parties"; while the SNP is confined to Scotland, Labour no longer competes in the south of England, the Tories no longer compete in the north of England while the Liberal Democrats, he will insist, compete nowhere.

This morning, Nick Clegg will unveil the key themes of his party's election campaign with the publication of the front page of the Lib Dems' manifesto. The full prospectus will be released once the short campaign gets under way in April.

In a speech in Oxford, the Deputy Prime Minister will place education at the heart of his bid for power with a pledge to protect spending from nursery to college south of the border throughout the next parliament to 2020.

It will be followed by four further promises to balance the budget "fairly", to cut taxes by raising the tax-free allowance to £12,500, to invest £8bn in improving the NHS in England, and to protect Britain's environment.

"Five priorities for five years. Five steps on the path to a stronger economy and a fairer society," Mr Clegg will say.

While Lib Dem sources said they were not setting out "red lines" for any coalition talks after the election on May 7, they made clear the party would fight "tooth and nail" to deliver them if it were part of the next government.

"These are our absolute top priorities. These are the priorities that we will fight with every breath we have to deliver. We'd expect to deliver them in a coalition," a senior source said.

The Lib Dems also dismissed suggestions the party had lost credibility on education after breaking its pledge in 2010 to oppose any increase in university tuition fees.

"Don't judge us by the one policy we couldn't deliver. Judge us by the policies that we did deliver," insisted the source.

This afternoon in Fort William, Willie Rennie, the leader of the Scottish Liberal Democrats, and Charles Kennedy, the former party leader, will reveal the Scottish party's manifesto front page, which will have an extra pledge on delivering Home Rule for Scotland.

Meantime, David Cameron will be making a speech to business leaders in Derby before visiting companies in the Midlands.

The Prime Minister said: "We are building a more resilient economy to benefit hard-working people across the Midlands, from its great cities to the stunning countryside of the Derbyshire Dales. We are already seeing more jobs and greater growth in the region but we want to see more. That's what our long-term economic plan will do; it will help the region build on its success and create new opportunities through massive investment in infrastructure and housing."