(Bloomberg) -- Theresa May briefed her Cabinet on Sunday evening that there was little prospect of cross-party Brexit talks yielding a workable alternative plan to the one that Parliament overwhelmingly rejected last week.

Instead, according to two people who were on the conference call between May’s most senior ministers, she said she would seek changes to the Irish backstop section of the deal she’s negotiated with the European Union. The goal would be to secure enough to get pro-Brexit members of her Conservative Party and her sometime allies in the Democratic Unionist Party back on her side.

The risk is that the EU has repeatedly ruled out re-opening the divorce deal it took 18 months to negotiate. May’s stance is bad news for investors who have been hoping that cross-party talks would yield a Brexit policy that keeps closer ties to the bloc.

The consensus on the call was that the things the opposition Labour Party has publicly asked for, including maintaining a customs union with the EU, would split the Conservative Party if May agreed to them.

Further, Labour leader Jeremy Corbyn has refused to take part in talks unless May rules out a no-deal Brexit and continues to wield the threat of a confidence vote against the government. That has left the government doubtful that the party could be counted on.

An extension of the Article 50 process governing Britain’s departure from the EU wasn’t discussed on the call, according to one of the people.

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