Chancellor Jeremy Hunt has announced that he is bringing forward measures from the Medium-Term Fiscal Plan that will support fiscal sustainability.
It was announced at 6am on Monday that the plan, which had due to be delivered in Monday, October 31, was being brought forward by two weeks.
The move will be seen as an attempt to reassure the financial markets after weeks of turmoil in the wake of former chancellor Kwasi Kwarteng's £45 billion mini-budget tax giveaway.
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Following his surprise appointment on Friday, Mr Hunt effectively tore up Ms Truss and Mr Kwarteng's previous economic strategy to cut taxes in an attempt to boost growth.
Instead, he warned that taxes would have to go up while spending would rise less quickly than had previously been planned.
Among the measures announced by Mr Kwarteng expected to be ditched are his promise to bring forward a 1p cut in the basic rate of income tax to April.
It has been announced that the statement will be delivered at 11am on Monday (October 17), followed by an address to the House of Commons at 3.30pm.
A statement from the Treasury said: "It follows the Prime Minister's statement on Friday, and further conversations between the Prime Minister and the Chancellor over the weekend, to ensure sustainable public finances underpin economic growth.
"The Chancellor will then deliver the full Medium-Term Fiscal Plan to be published alongside a forecast from the independent Office for Budget Responsibility on 31 October. "
The Chancellor met with the Governor of the Bank of England and the Head of the Debt Management Office last night to brief them on the plans.
The pound has jumped higher on news that new Chancellor Jeremy Hunt is to make an emergency statement on Monday to calm the chaos in the financial markets.
Sterling leapt to 1.129 US dollars at one stage, having kicked off more nervously, dipping to 1.122 against the greenback in overnight trading ahead of what many have feared would be a testing day on markets.
The Treasury's announcement of an emergency fiscal statement came before markets opened for the first time since the Bank of England ended its government bond-buying scheme, with all eyes on the reaction in gilt trading.
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