This article is more than 1 year old

This article is more than 1 year old

Britain’s economy will suffer rising unemployment and falling household incomes that would trigger a recession should Theresa May fail to secure a deal to prevent the UK crashing out of the European Union next year, according to analysis by the global rating agency Standard & Poor’s.

Property prices would slump and inflation would spike to more than 5% in a scenario that S&P said had become more likely in recent months following deadlock with Brussels over a post-Brexit deal.

In a warning that included a possible downgrade to the UK’s credit rating, which would bring with it an increase in the Treasury’s borrowing costs, S&P said it still expected both sides in the Brexit talks to come to an agreement before next March, when the UK is scheduled to leave the European Union.

But it warned that the chance of a “no-deal” Brexit had risen in recent months to such an extent that it needed to warn international investors about the potential challenges ahead.

The S&P report said:

Unemployment would rise from current all-time low of 4% to 7.4% by 2020 – a rate last seen in the aftermath of the financial crisis;

house prices would likely fall by 10% over two years;

household incomes would be £2,700 lower a year after leaving without a deal;

inflation would rise, peaking at 4.7% in mid-2019;

London office prices could fall by 20% over two to three years, similar to the decline following the 2008 financial crash.

Negotiations with the EU are about to enter the final few weeks, and while May has said an agreement is 95% complete, crucial areas, including the fate of the Northern Ireland border, remain unresolved.

A no-deal Brexit would shorten the odds on a long UK recession Read more

A demand by EU negotiator Michel Barnier for a backstop that would keep the Irish border open to trade, even if that meant separating the province from the mainland and creating a border in the Irish sea, has been rejected by the prime minister.

The impasse has fuelled doubts that a deal can ever be agreed in what time is left before each side must seek ratification.

S&P Global Ratings credit analyst Paul Watters, said: “Our base-case scenario is that the UK and the EU will agree and ratify a Brexit deal, leading to a transition phase lasting through 2020, followed by a free trade agreement.

“But we believe the risk of no deal has increased sufficiently to become a relevant rating consideration. This reflects the inability thus far of the UK and EU to reach agreement on the Northern Irish border issue, the critical outstanding component of the proposed withdrawal treaty.”

Coming only a day after the chancellor said the failure to secure a deal would force him to hold an emergency budget, S&P’s analysis joins a welter of independent reports that forecast that a split from the EU without a deal will deala serious blow to the prospects of the UK economy. Last month rival agency Moody’s said the risks to the British economy had “risen materially” in recent months.

Failure to agree a deal with Brussels would lead to a sharp fall in the value of the pound, triggering higher inflation and a squeeze on real wages lasting for as long as three years, it warned.

Adding to the weight of opinion, the International Monetary Fund and and the OECD have also said that crashing out of the EU without a deal was a material risk to the UK, the EU and the global economy.

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The warnings are likely to be dismissed by leading Brexiteers as an extension of the Treasury’s “project fear”, which predicted steep falls in household incomes, house prices and inflation.

Jacob Rees-Mogg and Iain Duncan Smith told the chancellor ahead of the budget that he was being too gloomy about Britain’s economic prospects outside the EU, even if it meant coping with trade barriers at EU border posts.

Rees-Mogg argued that Britain’s economy would be set free by leaving the EU, and though he preferred a deal to secure frictionless trade, this would be counterproductive if it tied the UK to EU rules for many years.

But Britain’s national income has already grown more slowly this year than expected prior to the EU referendum, with GDP growth below its previous trend of 2% to 2.5% and with wages only just inching ahead of inflation this year.

S&P said leaving the EU without a deal would make matters much worse, pushing the UK into a moderate recession lasting between a year and 15 months, with GDP contracting by 1.2% in 2019 and 1.5% in 2020. After that, the economy would return to growth, it said, though the pace of growth would be moderate.

“By 2021, economic output would still be 5.5% less than what would have been achieved in a scenario with an orderly exit and transition period for the UK,” it said in its report, Countdown To Brexit: No Deal Moving Into Sight.

S&P said high street banks would be caught up in the downturn, though efforts to shore up their reserves over the last eight years would provide protection against rising corporate insolvencies and weaker house price values.

Housing associations would also come under financial pressure from a fall in house values. Meanwhile, insurers would need to plan for a downgrade in the UK’s credit rating, which would increase their borrowing costs.