Head of OBR says officials should have told it about spending commitments in Jeremy Hunt’s pre-election budget

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Treasury officials may have broken the law when they failed to alert the Office for Budget Responsibility about £9.5bn of spending that should have appeared in the March budget, MPs have been told.

Laws governing how the Treasury gives information to the OBR could have been breached when civil servants kept spending commitments under wraps, the government’s independent economic forecaster said.