Is the revocation of Article 50 by the prime minister becoming more likely?

After more than two years of talks, could the UK be about to call time on Brexit by revoking Article 50?

What does “revoking Article 50” mean?

The Lisbon Treaty set out the rules of EU membership, and Article 50 was the part that dealt with quitting the bloc.

If a member state invokes Article 50, as the UK has, a two-year period begins in which the departing member must secure a withdrawal agreement to avoid leaving with no deal at all.

Revoking it means reversing that action, and going back to being a member state again.

While the Lisbon Treaty does not specifically set out issues relating to revocation, the European Court of Justice has ruled the UK can do it unilaterally, without the permission of the other 27 EU member states.

Does Theresa May want to do it?

Almost every single thing Ms May has said to date suggests not. For the last two years it has been specifically ruled out.

Revoking Article 50 could well further undermine the already severely weakened Tory party unity, potentially causing fatal damage.

So the government has always stuck to the line that leaving with a deal is the best option.

Is that changing?

There has been speculation that it is. When Theresa May put out a filmed statement on Sunday night she made clear that the choice ahead of MPs now is a choice between some form of her deal on one hand and no Brexit on the other.

This is based on the reality that the UK is requesting a further extension to the Article 50 negotiating period this week, and theoretically if the EU does not grant one, the UK would drop out of the EU with no deal on Friday night.

It is likely that the EU will grant one, but it is just possible that one of the 27 member states may veto it – France has been particularly bullish. The EU may also attach tough conditions to a further extension.

The only thing the PM could do to avoid a no deal if an extension is not forthcoming, or only comes with politically unacceptable conditions, is to revoke Article 50 altogether.

Are we able to revoke Article 50 at the drop of a hat then?

Possibly. Europe says it is within the gift of a member state to invoke and revoke Article 50 unilaterally, but domestically things get more complicated.

Ms May once tried to invoke Article 50 without consulting parliament and was taken to court by campaigner Gina Miller.

Ms Miller won her case. That means it could be difficult for the prime minister to revoke it without consulting parliament.

When MPs voted on revocation most recently, it was heavily defeated, though there were a large number of abstentions.

While most Tory MPs are likely to vote against revocation in any circumstances, a motion put forward by the government might do better than previously.

If we did it what would it mean for Brexit?

In legal terms Brexit would be off the cards. The default position would be that it is no longer happening and we remain a member state on the same terms as before.

Politically, the exact opposite is true. Brexit would likely dominate all political debate and there would be a major backlash against the political classes for their abject failure of governance.

Ms May would probably depart swiftly, replaced by a new Tory leader and prime minister chosen from the very Brexit-driven Conservative membership.

The re-triggering of Article 50, or at very least an election within a year or two based on the future of Brexit, would be likely.

If we still wanted to leave after revocation would it mean another two-year negotiating period?

Again this isn’t clear. Article 50 is vague on a lot of things, because when it was written no one expected it to be triggered. So the EU is effectively making up the rules as we go along. But there is a case to suggest that once revoked, a re-triggering would not necessarily be followed by a further two-year period, if both sides had agreed to a withdrawal agreement.

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