Britain set a hard deadline of December 2020 on Tuesday to reach a new trade deal with the European Union, betting that the prospect of another Brexit cliff-edge would force Brussels to move more quickly than usual to seal an accord.

Prime Minister Boris Johnson will use his control of Parliament to outlaw any extension of the Brexit transition period beyond 2020 — his boldest move since winning a large majority in last Thursday's election, and one that spooked financial markets.

In Brussels, officials said the timetable was "rigid" and likely to limit the scope of any deal.