Prime Minister Liz Truss and her Chancellor Kwasi Kwarteng spent the day defending their policy after a dramatic week that saw the pound slump against the dollar and the Bank of England forced to step in and take action.
The financial impact of the mini-budget is larger than a typical budget, but there has been no assessment by the OBR, according to the letter by Conservative MP Mel Stride, who chairs the cross-party Treasury Select Committee.
He said that the next OBR forecast should be brought forward and that the chancellor's next financial statement on 23 November should also be moved forward to as early as possible, given the uncertainty within markets. OBR publicly confirmed on Thursday that it had sent Chancellor Kwasi Kwarteng a forecast when he took office, but was not commissioned to do so.
The independent OBR forecast gave an indication of the health of the nation's finances and there were calls for a forecast to be published in the last week after Prime Minister Liz Truss spoke to a number of BBC outlets this morning, which saw her insist that the tax cuts outlined in the mini-budget were the right plan.
The message on WhatsApp contained a list of talking points that would defend the government's handling of the economy, including the need to emphasise that the economy was already in decline and the government needed to act urgently.