BRUSSELS - The European Commission said it was determined to quickly reach a deal with Britain on a future economic and trade relationship, but underlined it would have to ensure fair competition.

"We are fully concentrated on making the most out of this week's negotiating round... we share prime minister Johnson's desire to reach a deal quickly. We will do everything in our power to reach an agreement," a Commission spokesman told a regular news briefing.

He said a no-deal Brexit would "inevitably create barriers to trade and cross border exchanges that do not exist today" and noted the EU wanted a future relationship agreement to ensure fair competition.

The EU wants to know what state aid rules Britain will apply in the future to make sure the British government does not help the country's companies undermine EU ones through unfair financial help.

"I finally point out that while we are determined to reach an agreement with the UK, the EU will be ready - in the event of a no deal scenario - to trade with UK on WTO terms as of the first of January, 2021," the spokesman said.

(Reporting by Jan Strupczewski, John Chalmers, Marine Strauss and Kate Abnett) ((jan.strupczewski@thomsonreuters.com; +32 2 287 68 37; Reuters Messaging: jan.strupczewski.reuters.com@reuters.net))