Election campaigning is to focus on the economy as Labour and the Tories attack each other’s plans before independent analysts present their verdict.
Labour leader Ed Miliband will claim the Tories are planning “the biggest cuts anywhere in the developed world”.
But Conservative Chancellor George Osborne highlighted what he called the “frightening” cost of a Labour government supported by the SNP.
The Institute for Fiscal Studies is to assess pledges reports BBC.
It will release its analysis of the policies presented by the Conservatives, Labour, the Lib Dems and the SNP.
However, BBC political correspondent Ben Geoghegan said it was “unlikely to settle what are some of the most contested issues in this election campaign”.
Labour highlighted an analysis from the International Monetary Fund, claiming it showed Conservative cuts planned for the next three years would be “bigger than anywhere else among the world’s 33 advanced economies”.
Mr Miliband will claim spending cuts outlined in last month’s Budget would be “double the pace next year than this year”.
At an NHS rally in Leeds, he will say: “The Tories are committed to the most extreme spending plans of any political party in generations.
“It is a plan so extreme that far from protecting the NHS they would end up cutting the NHS.”