It is understood that 95% of the EU-UK future relationship treaty has been completed, but there remain large gaps on key stumbling blocks including fisheries and how disputes will be solved.

Despite progress, member states are now considering whether or not an agreement that might be reached in the coming days will have to be applied provisionally from 1 January and ratified later, because of the shortage of time.

The EU's chief negotiator, Michel Barnier, was due to brief member states this morning, but because a senior member of his team tested positive for coronavirus yesterday the briefing was given by European Commission Secretary General Ilze Juhansone.

It is understood that member states were told that 95% of the text was complete but there were still big gaps on fisheries, the so-called level playing field, governance and how disputes will be solved.

There is also growing concern that the process will not have enough time.

The transition period ends at 11pm on 31 December and any deal will have to go through a series of time-consuming legal procedures, including ratification by the European Parliament.

On the one hand, some member states say emergency no-deal contingency plans must now be published. On the other, officials are looking at ways to get around the time problem.

One idea is for any agreement to be provisionally applied from 1 January, with the legal and ratification procedures happening later, perhaps by the end of January.

The UK would have to give its consent.

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The other problem is whether or not the treaty will be regarded as touching only exclusive EU competences, such as trade and agriculture, or whether it also involves competences normally reserved by member states, such as aviation.

Then it would be what is called a "mixed" agreement. But traditionally mixed free trade deals have to be approved by all 27 member state parliaments, and some regional ones as well.

That would mean it could take two years for the treaty to come into force.

Either way, the gaps are still so wide that member states believe a no-deal outcome is still a highly possible scenario.