LONDON (Reuters) – Goldman Sachs said it sees a 50 percent probability of Prime Minister Theresa May getting a Brexit divorce deal ratified, adding that lawmakers would ultimately block a no-deal exit if needed.

Unless May can get a Brexit deal approved by the British parliament, then she will have to decide whether to delay Brexit or thrust the world’s fifth largest economy into chaos by leaving without a deal.

Goldman said it saw the probability of a no-deal exit at 15 percent and the probability of no Brexit at around 35 percent.

“There does exist a majority in the House of Commons willing to avoid a ‘no deal’ Brexit (if called upon to do so), but there does not yet exist a majority in the House of Commons willing to support a second referendum (at least at this stage),” Goldman said in a note to clients on Friday.

“The prime minister will repeatedly try to defer the definitive parliamentary vote on her negotiated Brexit deal, and the intensification of tail risks will continue to play a role in incentivising the eventual ratification of that deal.”