Angry expat Britons await PM May in Italy

Expatriate Britons have gathered in Florence to voice their frustration at how Brexit will affect them, awaiting the British prime minister's arrival in the Italian city to set out her vision for future ties with the European Union.

May will try to rescue the stalled talks over terms for Britain's exit from the EU in a speech on Friday that will be scrutinised to see if she can offer enough to EU negotiators to persuade them to move forward.

Outside an imposing 14th-century church in the centre of the Tuscan city, protesters waved EU flags and posters showing May holding a burning passport.

They called for the rights of British citizens living in other EU countries to be protected.

Rachel Pugh, a 48-year-old from north Wales who has lived in Florence since 1991, said she was worried about losing her rights to a pension in the future and had been left uninformed by the British government.

"Who do we ask? The Tooth Fairy? Father Christmas? The Easter Bunny? Who can we trust? None of them," she said.

"We couldn't vote. We're invisible, in limbo."

Negotiations, which began three months ago, have reached an impasse over the divorce, including the issue of how much Britain will have to pay to unspool more than 40 years of economic and political integration in the EU.

"The UK's departure from the EU is inevitably a difficult process, it is in all of our interests for our negotiations to succeed," May will say, according to advance extracts of her speech.

"The eyes of the world are on us but if we can be imaginative and creative about the way we establish this new relationship ... I believe we can be optimistic about the future we can build for the United Kingdom and for the European Union."

The BBC reported May would say Britain is willing to pay 20 billion euros ($A30 billion) to the EU during a post-Brexit transition period but only if it has access to the bloc's single market.