The ministry will spend whatever is necessary to make sure the UK is ready for Brexit, Downing Boulevard has said.
A No 10 spokesman said £250m of new money had been allocated this year to cram for leaving the EU, «including the possibility of a no-deal scenario».
Speaking at Prime Curate’s Questions, Theresa May said «where money needs to be spent it ordain be spent».
Earlier, Chancellor Philip Hammond said funding for a no-deal scheme would not happen «until the very last moment».
He suggested it was not judicious to spend money — which could alternatively go to the NHS or schools — at this echelon on an outcome which may or may not happen, merely to «send a message» to the EU.
In response, particular Tory MPs have criticised the Treasury, one accusing it of «incompetence» and another introducing the EU would not listen to the UK unless it was sure it was seriously preparing for the possibility of sabbatical in March 2019 without a negotiated agreement.
The BBC understands a row broke out at Tuesday’s Cupboard meeting over the issue of contingency funding in the event of a «no deal» grand scheme in the Brexit negotiations.
The BBC’s political editor Laura Kuenssberg said two unconventional cabinet sources confirmed there was a «robust» exchange. Downing Concourse denied there was a row but acknowledged there had been a brief discussion.
She totaled that how much to spend on preparations for leaving the EU without a deal, and when to waste it, had become a new faultline in the Tories’ divisions over Brexit.
Mrs May announced the £250m Brexit contingency breading in response to a question from ex-leader Iain Duncan Smith, who sought certitudes «all necessary monies» would be spent in case of a no-deal outcome.
«We are grooming for every eventuality,» she told MPs. «We are committing money to prepare for Brexit grouping a ‘no deal’ scenario.
«The Treasury has committed over £250m of new money to spheres like DEFRA, the Home Office, HMRC and DfT in this financial year for Brexit preparations and in some if it should happens, departments will need to spend money before the relevant legislation has accorded through the House.»
Mrs May said the UK was striving for a good deal with the EU and spurned claims from a Labour MP that she was «running scared» of her backbenchers and «ramping up» talk far the odds of there being no deal.
Two hours earlier, the chancellor — who has been accused of being too pessimistic beside Brexit — told the Treasury committee of MPs that he was «committed» to supporting hang ons prepare for Brexit but said it would be premature to spend money now on the assumption there liking be no deal between the UK and EU.
«We are prepared to spend when we need to spend against the contingency of a ‘no transaction’ outcome,» he said.
«I am clear we have to be prepared for a ‘no deal’ scenario unless and until we accept clear evidence that this is not where we will end up.»
«What I am not instant to do is allocate funds to departments in advance of the need to spend,» he added.
«Every produce we spend on contingency planning on a hard customs border is a pound we can’t assign on the NHS, social care or education. I don’t believe we should be in the business of making potentially nugatory loss until the very last moment when we need to do so.»
Illustrating what he said was one worst case scenario for a «no deal», he asserted there could be no air travel taking place between the UK and the EU on Brexit day — 29 Hike 2019 — but added that he did not see that as likely to happen, even if the UK/EU talks go to the wall to reach agreement.
The current state of Brexit negotiations were a «cloud of uncertainty» dallying over the UK economy, he said, which could only removed by onwards and the EU agreeing to begin talks on its future relations with the UK.
One ex-minister, David Jones, has said billions should be set aside in November’s Budget for a «no attend to» scenario, arguing that if this did not happen it would be seen as a «a grapheme of weakness» by EU leaders.
And Jacob Rees-Mogg said the Treasury’s conduct with connection to Brexit had been «incompetent bordering on the dishonest» and planning for all possible follow-ups was a necessary «insurance policy».
«If you think the EU is claiming 100bn euros from us, to make credibility for the no deal scenario we have to show that it’s real and it can turn up,» he said.
«And most of the money that would be spent for no deal wish be money that’s needed for the end result anyway.
«So, changes to the borders, trades to customs and excise, will need to take place regardless of whether there is a act on or not. So it’s not wasted money, it will be money that’s very well fatigued.»
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