The move will be unveiled in one of the stronger areas of Ukip support, and underlines the extent to which Cameron is determined to squeeze what he believes is a weakening of Ukip voters’ resolve in the south. A serious crack in the Ukip vote – which until now has been resilient – is a precondition of a Tory majority government.

Cameron’s repeated warnings to the English of the dangers of the Scottish National party holding the balance of power at Westminster has been directed primarily at the same Ukip vote, and Conservative strategists insist it is working on the doorstep.

Setting out plans for an English income tax, Cameron will begin by referring to changes in Scotland. “Soon the Scottish parliament will be voting to set its own levels of income tax – and rightly so – but that has clear implications. English MPs will be unable to vote on the income tax paid by people in Aberdeen and Edinburgh while Scottish MPs are able to vote on the tax you pay in Birmingham or Canterbury or Leeds. It is simply unfair.”

The Scottish Labour leader, Jim Murphy, warned that Cameron was playing with fire by using what he described as crude and cheap tactics. “You don’t defeat Scottish nationalism with David Cameron’s English nationalism. You do it with social solidarity,” Murphy said at a rally in Scotland.

Murphy was later joined by the former Labour prime minister Gordon Brown who, speaking in Kirkcaldy, again insisted that Labour and not the SNP would write a budget for social justice.

However, Cameron will ignore warnings that he is stoking division in the union. He will argue that the move is a consequence of the Smith commission’s November 2014 recommendation that the Scottish parliament should set income tax rates and bands in Scotland and retain all income tax revenue raised there.

Cameron will say: “We do not support English nationalists. We do not want an English parliament. We are the Conservative and Unionist party through and through. This manifesto simply recognises that the democratic picture has got more complicated in the UK so, beyond our main manifesto, English voters deserve one document, clarifying in black and white what they can expect.”

At present income tax is not devolved to Wales and Northern Ireland so MPs from these two countries would continue to be involved in voting on the rate.

The prime minister will also promise a timetable for the delivery of a system in which English MPs would only be able to vote on laws affecting England with proposals brought forward within the first 100 days of a new Conservative government and fully implemented in time for the first budget of the new parliament in March 2016. The move would come alongside the publication of changes to the standing orders of the House of Commons that would make English votes for English laws a reality.

William Hague, the former foreign secretary, who is due to appear alongside Cameron, will set out the timetable for delivering the English votes for English laws system. He will say: “This is not a vague promise to make this change some time in the future – this is a plan ready to be implemented. We will table our proposals within the first 100 days after the general election.”

In the party’s English manifesto Cameron will suggest that more than 60% of new jobs after the election will be created outside London and the south-east. “We will ensure that working people across England benefit from our long-term economic plan: in the great manufacturing plants of the West Midlands and north-east, in the tech startups from Bristol to Manchester, in the tourist and defence industries of the south-west and Wales and in the life science labs of the east of England.”

In Scotland, Brown launched a strong attack on the SNP, saying there was no chance of a deal between Labour and the SNP and adding that the SNP put showing that Westminster could not deliver on issues such as the bedroom tax ahead of providing real help for the poor.

He said Labour would provide 171 food banks in Scotland with £5,000 each within 24 hours of Labour being elected.

Brown has also written to 350,000 households to warn that SNP plans for “devo max” – enhanced devolved powers – would mean sharp cuts in public spending, including a threat to the state pension.

Speaking in Kirkcaldy, he said: “The SNP wake up in the morning thinking of how to make Scotland independent. We wake up in the morning thinking of how to advance social justice and that is why it has to be the Labour party which is writing the first budget and not Alex Salmond, who does not share our sense of priorities and who must share the blame for failing to address poverty as first minister.

“The SNP dream is about constitutional change. Our dream is about social change.”