EU Council President Donald Tusk has warned European leaders to start listening to one another amid a "real" risk of a break-up. Tusk said that the UK's negotiations with the bloc are at a "critical moment", and urged officials to handle talks with care.

"After my talks today with President Iohannis [of Romania], Prime Minister [David] Cameron and President [Francois] Hollande and before meeting Prime Minister [Alexis] Tsipras, Prime Minister [Bohuslav] Sobotka [of Czech Republic] and Chancellor Merkel tomorrow, I have only one political reflection. This is a critical moment," said Tusk.

"It is high time we started listening to each other's arguments more than our own. The risk of a break-up is real because this process is very fragile and must be handled with care. What is broken cannot be mended," he added.

Cameron is holding talks with Hollande this evening (15 February) as he seeks support for his reforms from fellow leaders as part of a European tour. His discussions with the French leader will focus on concerns from Paris at Downing Street's demands to shield UK banks from rules governing the eurozone.

On 18 February, the Tory leader will head into a two-day summit in Brussels, which effectively marks the beginning of the referendum battle. If Cameron strikes a deal at the meeting, he will hold a Cabinet meeting immediately on 19 February, according to a Press Association report.

Britain's EU referendum is reportedly the top item on the agenda at the Brussels summit and an agreement could be reached on the evening of 18 February. Amid rising Euroscepticism, Number 10 has insisted that nothing is final until an agreement is reached. Foreign Secretary Philip Hammond said that "very big issues" remain on the table.

Some 49% of Britons would vote to stay in the EU compared to 41% who would choose to leave, according to an ITV News poll undertaken by ComRes. Despite the positive reading for the "remain" camp, support for Britain to stay in the bloc has been slashed by 5% since the previous survey, which was done before Cameron's EU deal was announced.

Warning of the consequences if Britain decides to leave the 28-member EU, Tusk said: "At stake is also the future of our European Union, where we will all have to decide together and where we cannot and will not compromise on European values."