Britain's negotiating position on the European Union budget is becoming increasingly unstable, an expert has said.
The warning came after David Cameron yesterday outlined Britain's negotiating position, telling journalists in a joint press conference with Danish prime minister Lars Lokke Rasmussen that he wanted to see the size of the EU budget reduced.
"As we reduce our deficits, I think it is very important that we both argue to make sure that the European budget is, over time, reduced rather than increased," he said.
"We cannot ask members of the public to pay more in the UK and have to pay more in Europe as well."
Philip Whyte, senior research fellow at Centre for European Reform, warned that the arguments justifying Britain's ongoing rebate were being increasingly undermined, however.
"This is a perennial issue on which the UK finds itself alone," he told politics.co.uk.
"The UK has a rebate under the EU budget. But the UK's position is becoming increasingly unstable."
Mr Whyte warned that reforms of the common agricultural policy meant less and less of the EU budget was being spent on agriculture, the basis of Britain's rebate.
"As the share of the budget spent on agriculture falls, the source of that mismatch disappears," he explained.
Negotiations for the seven-year budgetary cycle, to be completed in 2013, are due to begin shortly.
A mid-term budget review is set to begin later this year.