Britain’s top civil servant has told government departments to ready themselves for a general election, as the U.K. parliament struggles to find a way to break the Brexit deadlock.

Sir Mark Sedwill is reported to have met with Whitehall chiefs this week to discuss preparations in case Prime Minister Theresa May decides to go to the country.

It comes just hours after William Hague, a former leader of the Conservative Party, warned that the prospect of a general election being called to break the stalemate should not be underestimated.

Sterling dropped on the news from $1.29851 at 6:30 GMT to trade at $1.29472 around 9 a.m. U.K. time.

Elsewhere, Citigroup has named a successor to its longstanding chief executive in Europe, Jim Cowles, who announced his intention to step down from the bank in September after 39 years.

David Livingstone, Citi’s chief country officer for Australia and New Zealand, will relocate to London to lead the bank in Europe, the Middle East and Africa. His appointment comes as at a crucial time for Citi, with the U.S. bank preparing its European operations for the UK’s impending departure from the EU trading bloc.

The days ahead: what to watch for…

Monday, Jan 21: May will have to present her plan B for Brexit on Monday. Members of parliament can propose amendments to May’s new plan from then.

Tuesday, Jan 29: British parliamentarians will be allowed to debate or vote on May’s new proposals and suggest any amendments to it.

It is at this point that pro-European politicians in the U.K. could hijack the Brexit process. Their coup reportedly includes plans to amend strict government motions to ensure they can dictate the future of the split.

Such a move was made possible by a controversial decision last week by the speaker of the U.K. House of Commons, John Bercow, who allowed Conservative politicians from outside the government to make changes to its plans.

For any coup to work, however, Bercow would have to suspend a parliamentary procedure, first implemented in the 1880s, which dictates that government business must always take precedent in the House of Commons.

If that happens, MPs will have an opportunity to vote on a bill proposed by Conservative europhile Nick Boles, which makes it legally impossible to force the U.K. out of the EU without a deal. The bill mandates an extension to the Article 50 notice period if MPs can’t agree a way forward.

Boles has said some government ministers back the plan because it would create “the space for a compromise by ruling out a no-deal Brexit”.

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