A senior European Union official said Sunday's target date for a Brexit deal might well turn into another missed deadline in the saga.  He added,  that the latest developments in the European Union –United Kingdom talks did not leave them "very optimistic".

"The only certainty I have is that January 1 comes after December. 31," the official said, referring to the date when Britain leaves the European Union's single market and customs union, leaving behind its current free trade arrangements with the 27-nation bloc.

The official, who took part in the Thursday-Friday summit of the European Union's national leaders in Brussels that briefly looked at the latest in Brexit, said gaps in talks on a new trade deal between London and the bloc were still "very very big.

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