ED Balls has come under a double attack for describing as a joke the notorious note left by the former Labour Government, saying there was no money left in the Treasury.

David Cameron, speaking at the launch of the Scottish Conservative manifesto in Glasgow, upbraided the Shadow Chancellor. He said: "Ed Balls saying this is some kind of a joke is frankly the most appalling thing I have heard in this election campaign so far."

The Prime Minister added: "I'm not surprised he was Ed Miliband's third choice to be his Shadow Chancellor. Frankly, he is the country's last choice to be put in charge of this nation's finances."

Danny Alexander, the Liberal Democrat Chief Secretary to the Treasury, also seized on Mr Balls's remarks, saying: "Ed Balls may think it's funny that Labour left the country with no money but it's no laughing matter for the millions of people who've been working so hard to turn the economy around.

"Rather than laughing about the state of the economy under Labour, Ed Balls should be apologising for it," he added.

In a BBC interview earlier this week, the Labour frontbencher dismissed the memo, left by his colleague Liam Byrne in 2010, as "a jokey note", stressing: "It was supposed to be a piece of humour."

He added: "In fact, in that year, the Government spend hundreds of billions of pounds, so of course the money hadn't run out, but there was a large deficit and we had to get it down and we needed to get it down in a fair way."

Meantime in a campaign speech in Birmingham, Mr Balls said working families would lose out to the tune of £1439 each if the Tories won the election because Mr Cameron had made £25bn a year of "fantasy and unbelievable promises".

The Shadow Chancellor said the Conservatives' "panicky promises" such as raising annual NHS funding by £8bn by 2020 and spending £6.5bn to raise the income tax allowance to £12,500, would leave people out of pocket.

Labour, he explained, had carried out an "audit" of Tory policies, which also showed that plans to allow workers to take three days' annual leave for paid volunteering would cost £1.2bn and raising the threshold of higher rate tax to £50,000 would cost £3.9bn.

"Everyone knows it will be working families, who end up paying the price again if the Tories win the election," added Mr Balls.

Elsewhere, Ken Clarke, the former Conservative Chancellor, warned his party against pursuing direct personal attacks against its opponents.

In an interview with the left-wing New Statesman magazine, Mr Clarke stopped short of specifically criticising his colleague Michael Fallon, the Defence Secretary, who last week accused Ed Miliband of being prepared to "stab the UK in the back".

But when asked about Mr Fallon's attack, the ex-Cabinet Minister said: "I won't get onto that but personally I disapprove of personal attacks on your opponents. I've never done that. I also think it costs you votes if either side goes in for personal attacks on the other side."