David Cameron is launching the Conservatives' first English manifesto, with a promise of changes to ensure that English MPs have the final say on income tax rates in England.

And in a bid to win Ukip supporters back his party, he's warning that a Labour government backed by the Scottish National Party would result in 'a return to uncontrolled immigration'.

The English manifesto sets out a timetable for the implementation of Conservative plans for English votes for English laws in the House of Commons and a promise to extend it to financial issues.

From the Budget expected in March, whenever taxes have been devolved to Scotland, Conservative plans would require the consent of English, Welsh and Northern Irish MPs to set the level in those parts of the United Kingdom.

Mr Cameron is expected to say: '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. And with English votes for English laws we will put it right.'

Turning his fire on Labour over immigration in an article for the Daily Mail, Mr Cameron said: 'The only way Ed Miliband can get into Downing Street is if he is propped up by the SNP - and they have made clear that they want higher levels of immigration. It's clear: Ed Miliband in Downing Street would increase immigration, not reduce it.

'And if you're someone considering voting Ukip because you want a referendum on Europe and controlled immigration, remember that a vote for Ukip makes it harder for Conservatives to win - and much more likely for Ed Miliband and the SNP to get into government. Then you will get no referendum, and a return to uncontrolled immigration.'