BRUSSELS,? - Britain will need years to negotiate a future trade deal with the European Union after it quits the bloc and will be landed with a "very hefty bill" from Brussels on leaving, EU chief executive Jean-Claude Juncker said on Tuesday.

Noting that the Brexit talks expected to be launched next month would last two years before Britain withdraws from the bloc, Juncker said in a speech to the Belgian parliament: "To agree on the future architecture of relations between the United Kingdom and the European Union, we will need years."

Referring to payment the EU will seek from London to cover future EU spending to which Britain has committed as an EU member, he added: "The British should know this, they know this already, that it will not be at a discount or at zero cost. The British must respect commitments they were involved in making. So the bill will be, to put it a bit crudely, very hefty."