Is Ed Miliband’s fiscal responsibility promise just a Houdini lock?

Ed Miliband was on bullish form at Granada’s studios in Manchester launching Labour’s manifesto. You wouldn’t know it had been a tortuous business getting here, but ask anyone involved and it most certainly was.

He was performing the traditional political trick of nicking the other side’s political clothes – in this case the Tories’ Sunday best: their reputation for fiscal prudence. Ed Miliband said the Conservatives “are now the irresponsible party in British politics” – which rather begs the question of who used to have that mantle.

I asked Ed Miliband if the proudly proclaimed “fiscal responsibility lock” on page one of the manifesto was actually a bit like one of Houdini’s locks, something Ed Miliband knew exactly how to unpick.

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The IFS says his rules are so deliberately vague that they could mean £18bn worth of additional cuts across the piece, or zero.

Ed Miliband insisted there would be cuts and there would not be zero cuts, but he still has a lot of wriggle room – he could be cutting £1bn or close to £20bn. The IFS says it is still unclear and he told us nothing really new on this today.

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