The U.K. may be edging closer to a historic exit from the European Union (EU), with a new poll suggesting that more of its citizens would vote to leave than stay.
The potential for an unprecedented departure has raised real concerns among British businesses and investors, which have benefited from the trading benefits associated with EU membership. And yet businesses have been warned to stay out of the campaign by those close to Prime Minister David Cameron, according to a report in the Financial Times Monday.
While the referendum on EU membership does not have to take place before the end of 2017, the campaign to persuade the U.K. public has already begun, and the subject looks to be close to the top of the agenda for months.
Against this backdrop, Cameron and his Chancellor of the Exchequer, George Osborne, are attempting to renegotiate the terms of the U.K.'s membership with their EU partners. However, the more imminent issues of potential Grexit and the refugee crisis have preoccupied Europe over the summer, pushing U.K. concerns down the agenda.
Osborne told CNBC over the weekend there had been "quite a lot of willingness to engage with the U.K. and make this work for the whole of the EU" in discussions so far.
"Across Europe there's a recognition that Europe is not working as well as we'd like it to work for all of Europe's member states. There's widespread recognition that we need to do more to create a lasting, stable relationship between those who are in the euro zone and those who are outside the euro zone," he added.
Discussions may become more urgent, after the first poll conducted since the wording of the referendum question was agreed suggested a narrow lead for the Exit camp.
While 17 percent of those polled by Survation for the Mail on Sunday remained undecided, 43 percent would vote to leave the European Union, and just 40 percent to stay.
- By CNBC's Catherine Boyle