Sir Alan Budd, the first chairman of the Office for Budget Responsibility , said he believed the OBR had rebuked David Cameron because he "made an error'.
I think it could be regarded as something of a rebuke.
I think he is correcting a statement that the Prime Minister has made and the important thing is that the Prime Minister is attributing a view to the OBR which it doesn't hold and I think when that happens it is absolutely right to write to the Prime Minister and point out that he has made an error.
Sir Alan was talking to BBC Radio 4's PM program.
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Cloudy and mild tonight with cloudy skies again for most of us tomorrow.