On Friday a think tank, the National Institute of Economic and Social Research, said none of the three parties have been honest about the measures needed to deal with Britain's debt. It said spending cuts won't save Britain from further recession and tax hikes will be needed.

With the final TV debate now over and only six days before the election, all three leaders are now in the last leg of their campaigns.

Black says the prospect of a hung parliament – in which no party has a majority of seats – still seems likely.

Nick Clegg has said a hung parliament would be a good thing for Britain – and Black says British voters may feel the same.

"We could of course conclude from that, that that's actually what people want and that they're sort of buying Nick Clegg's line from the Liberal Democrats that what this economic crisis needs is a sort of government of all the talent – politicians working together, not working in a sort of partisan way against each other," says Black.

Former British Prime Minister Tony Blair is in Britain campaigning for the Labor party. The election is due to take place on May 6th.