The European Union says after a first day of talks on Britain's exit from the 28-member bloc that the clock is ticking on negotiations, but British Brexit minister David Davis said he's optimistic they will yield a swift and good outcome.

The Brussels talks began almost a year after Britain unexpectedly voted in a referendum to leave the EU and less than two weeks after Prime Minister Theresa May lost her overall majority in snap elections that raised questions about the stability of the government the EU faces.

"The clock is ticking," EU chief negotiator Michel Barnier told a joint news conference with Davis on Monday, adding that an orderly withdrawal was essential for both Britain and the EU. A fair deal for both sides was possible, he said.

He quoted the founder of the trading bloc that later became the European Union, Jean Monnet, as saying: "I am neither optimistic nor pessimistic. I am determined."

Davis, taking up the historical theme, quoted British wartime leader Winston Churchill.

"The pessimist sees difficulty in every opportunity, the optimist sees opportunity in every difficulty.

And so bridging between Churchill and Monnet I am certainly a determined optimist."

Davis said Britain's negotiating position had not changed as a result of his Conservative Party's poor showing in recent elections. Britain, he said, would seek to leave both the single market and the customs union and forge a separate trading agreement.

Professor of politics at the University of Kent Matthew Goodwin said there's a big debate going on about economics versus identity.

He told Mike Hosking the EU is not exactly riding high at the moment.

"There are lots of parties that also want their countries to either leave the EU, or have powers returned from Brussels back to the individual member states, so it's a really complex situation there."

Goodwin said there are those who want to retain the single market .

He said that's essentially putting jobs and the economy ahead of immigration which is a contentious issue for Britain.

"So what we're seeing is a big debate about economics versus identity, and the Government's going to have to try and tread what is a very rocky road."

LISTEN ABOVE AS MATTHEW GOODWIN SPEAKS WITH MIKE HOSKING