MPs face a “stark” choice between a short delay to Brexit – if they back Theresa May’s deal – or a much longer one if they reject it, a minister said.
David Lidington – Mrs May’s second-in-command – was speaking ahead of a vote later on delaying the UK’s departure from the EU on 29 March.
The PM will make a third attempt to get MPs to back her deal in the next week.
If it fails again, Mr Lidington said MPs would get two weeks to decide what they wanted to do instead.
The government would allow MPs to hold a series of votes on possible ways forward on Brexit, indicated the cabinet office minister.
But he warned that a longer extension would mean “a sustained period of uncertainty… which I fear would do real damage to the public’s faith in politics and faith in democracy”.
And it would also mean that the UK would have to contest the European Parliament elections in May, he added.
MPs will vote later on a motion calling for a three month delay to Brexit if MPs back Mrs May’s deal – or a longer one if MPs do not support it by 20 March, the day before the next EU summit.
Any length of extension has to be agreed by the EU.
European Council president Donald Tusk has indicated that the EU may be ready to offer a lengthy extension to negotiations if the UK wants to “rethink its Brexit strategy and build consensus around it”.
Mrs May is currently chairing a cabinet meeting to decide the government’s next moves on Brexit.
Northern Ireland’s Democratic Unionist Party – which twice rejected Mrs May’s deal in the Commons – earlier held talks with the government to see if a solution could be found allowing its MPs to support the PM in a future vote.
MPs voted on Wednesday evening to reject a no-deal Brexit under any circumstances.
No date has yet been set for the third so-called “meaningful vote”.
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