If Vince Cable wants to remain in Cabinet he must denounce Labour's economic policies in clear and unambiguous terms

By Tim Montgomerie
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Returning to a theme that he launched two weeks ago, we have renewed confirmation this morning from John Rentoul of simmering tensions at the top of the Labour Party. Mr Rentoul uses his Independent on Sunday column to insist they "everyone" at the top of Her Majesty's Opposition knows that there is a feud between the two Eds, Balls and Miliband. The only unknown thing, he writes, is the intensity of the feud.

The two Eds, however, seems more interested in forming an alliance with Vince Cable than repairing their own relationship. Two days ago the Labour leader told journalists that he had a textual relationship with the Business Secretary and the man very likely to be Lib Dem leader by the time of the next election. Today it's Mr Balls who is wooing Mr Cable. This is what he writes in the Sunday Mirror:

"In his heart of hearts, Lib Dem Business ­Secretary Vince Cable must know that Plan A is not working. After all, before the last election, he warned – with Labour – that David Cameron and George Osborne’s policies would backfire. And sadly our warnings came true. So let’s work together on new ideas to create jobs and build our way out of recession."

The ball is now firmly in Mr Cable's court. It's not enough for him to say that he simply supports existing Government policy. We need him to state clearly and very strongly that the fiscal policies of Ed Balls - which, by some estimates, would add £200 billion to Britain's debt burden - are irresponsible and that until Labour returns to fiscal sanity then Labour are unfit for office.

Let's hear it Mr Cable and soon. If we don't hear it we can only assume you are indeed preparing for some sort of alliance with the two Eds.

As President Hollande's retreat from his pre-election promises shows, there is no alternative in this current crisis to the kind of difficult deficit reduction path that Britain's Coalition has embarked upon.

10am update...

Vince Cable was just on Andrew Marr and didn't dampen speculation about him joining up with Labour. He described himself as a politician of the Left because, he said, he believed in fairness and distribution. Some on the Right believe in those things too! Janet Daley does a good job of attacking the idea that left equals compassion in today's Sunday Telegraph.