UK Stocks-Factors to watch on Dec 18

Dec 18 - Britain's FTSE 100 index is seen opening 36 points lower at 6,738 on Tuesday, according to financial bookmakers. * BREXIT: UK Prime Minister Theresa May said on Monday she would bring her Brexit deal back to parliament for a mid-January vote, pledging to get assurances from the European Union before then to break a deadlock over Britain's fraught efforts to quit the bloc. * ROYAL DUTCH SHELL: An Italian judge said on Monday oil majors Eni and Royal Dutch Shell were ful