The animosity between Ed Balls and Nick Clegg had previously been regarded as a major obstacle to the two parties joining up if there is a hung parliament after a general election.
I think they've [Labour] changed. I think there's nothing like the prospect of reality in an election to get politicians to think again and the Labour Party, which is a party unused to sharing power with others is realising that it might have to.
There is just no doubt in my mind that if there were a Labour-Liberal Democrat coalition, we the Liberal Democrats would absolutely insist that government would not break the bank.
Asked about Labour on the programme Mr Clegg said that if such a pact was formed, the Lib Dems would set out to restrain Labour from spending too much.
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