The likelihood of a disorderly Brexit has crept higher but that won’t deter the Bank of England from raising rates next week for the first time in a decade, even though many economists believe that would be a mistake, a Reuters poll showed.

There is now a 30 per cent chance Britain will leave the EU without a trade deal when two-year divorce talks end in March 2019, up from 25 per cent in a September poll, according to the median forecast in the latest Reuters survey of economists.

“It is in everybody’s interests that a transitional arrangement is put in place by 2019. Given the EU’s habit of finding a last-minute solution, we believe that a deal will be found. But the risk of failure is non-negligible,” said Peter Dixon at Commerzbank.

British Prime Minister Theresa May won a modest reprieve last week when European Union leaders signalled they were ready to move negotiations forward in the coming months.

But she now faces a political balancing act as she tries to meet EU demands for more concrete pledges on Britain’s divorce Bill without triggering a backlash from Brexit campaigners at home, some of whom would prefer she walk away from talks.

The overwhelming majority of respondents in the poll, however, said the most likely ultimate outcome was still an EU-UK free trade agreement, possibly with a transitional arrangement.

The second most probable outcome was Britain leaving without a deal and being forced to trade with the continent under basic World Trade Organisation rules, the poll showed.

Third was European Economic Area membership, under which Britain would pay to maintain full access to the EU single market – but without having any say over its policies. The least likely option was Britain reversing its decision to leave the European Union, the poll showed.

While the sample of respondents was different and slightly larger than the Reuters poll published on September 1, the overall conclusions about Britain’s likely future trading relationship with the European Union were the same.

There was no noticeable change among those who contributed to both polls although a majority increased their risk forecast.

European Council president Donald Tusk said on Tuesday it was up to Britain to determine if there would be a good deal or no deal and European Commission president Jean-Claude Juncker said they were not negotiating with London in a hostile way.

Britain’s economy has so far dodged the widely-predicted post-referendum recession but is now lagging, rather than leading, the other Group of Seven industrialised economies in the midst of a resurgence in the global economy.