In comments to journalists at the end of a European Council that focussed on the negotiations with the UK on Brexit, Costa admitted that the news coming out of this summit on the matter was "so-so", because "though there has already been progress in preparing the exit agreement, there was still no final agreement."

Although it was not possible to conclude an overall agreement at the summit that had at one point been presented as "the moment of truth", Costa said, he expected that a commitment would be made "in good time". This was, he said, "not a question of optimism [but] a question of realism", since the negotiations have progressed and "no one has an interest in there being no agreement".

According to the prime minister, since the Salzburg summit in September, many dossiers have been unblocked; what remains at this "final point" of the negotiations is the admittedly "delicate and difficult" issue of the Irish border with Northern Ireland.

"At this point, it's only a stitch in discussion, so I would say that the stars would have to be very badly aligned for us not to be able reach an agreement in good time.”

However, he added, and because "it is better to be safe than sorry, all member states and the EU are developing contingency plans with a view to responding to an eventuality of up to 11 p.m. on 29 March 2019 there is no agreement" when the UK is due to leave.

The EU’s heads of state and government agreed on Wednesday night in Brussels that there had not been enough progress in the negotiations with the UK, so ruling out for now the scheduling of a new extraordinary summit for November, as had been talked about.