A team of Icelandic negotiators left London on Friday after failing to reach a last-minute deal with Dutch and British officials to repay billions of euros of compensation for a collapsed online bank, a day before a destabilising referendum in Iceland on the issue.

Negotiations over easing repayment terms for the €3.9bn that the British and Dutch governments paid on behalf of Iceland to savers in the Icesave online bank had already broken down once last week, but “on-and-off” talks continued all this week, said a Dutch official.

The Dutch finance ministry said there were no further plans for talks with Iceland but it remained committed to finding an agreement. An official said signs from Reykavik suggesting fresh talks could take place as early as next week were positive.

Icelanders are expected to use Saturday’s plebiscite to reject a repayment plan agreed by the three sides last year. In the recent negotiations, aimed at reaching an agreement before the referendum, the Dutch and British had already made concessions beyond what it being voted on.

Opinion polls show most Icelanders are opposed to the deal, amid criticisms the terms are too harsh and questions over Iceland’s legal obligation to cover foreign bank deposits.

Since the 400,000 savers who were affected by the collapse in 2008 of Landsbanki, which ran Icesave, have already been repaid, the Icesave negotiations have not caused major public concern in the Netherlands or the UK. Both London and The Hague have however remained adamant that a deal must be reached and reject suggestions they are seeking harsh repayment terms.