Proposals by UK leader Tony Blair to break the deadlock over the European Union's budget have been criticised by several of the union's newest members.
Tony Blair: Big states should pay in a similar share of national income
Mr Blair suggests cutting the proposed EU budget for 2007-13, reportedly by shaving 10% from aid for new members and by accepting a trimmed UK rebate.
Prime ministers from the three Baltic states lined up to criticise the plan despite meeting Mr Blair on Thursday.
And Poland said it hoped to win German backing to oppose the plan.
Mr Blair meets four Central European leaders on Friday as he continues trying to sell the compromise.
Earlier, he predicted he would be "attacked from all sides".
It is believed a "slightly smaller" rebate will be proposed as a way of the UK making a "contribution to the cost of EU enlargement".
Under the terms of the proposed deal, the UK would not receive any rebate from poorer countries in central and eastern Europe.
The BBC's political editor Nick Robinson said: "In layman's terms [that] is the same as giving up part of the rebate".
Attempts last June to reach a deal on the budget collapsed when the UK rejected pressure to give up the rebate without a major reform of farm spending.
Speaking in Kiev before flying to Tallinn, Mr Blair said: "If we cannot get a large deal, which alters fundamentally the way the budget is spent, then... we will have to have a smaller EU budget.
'Price of leadership'
"None of this is going to be easy... Meantime, I will get attacked, probably from all sides, but then... that is part of political leadership."
He added that at the end of any budget deal, there needed to be "rough parity on a national income basis between Britain and like-sized countries".
Germany's new foreign minister, Frank-Walter Steinmeier, said he was "fairly confident" that the British proposal would provide a basis for consensus by the middle of the month.
But Polish Prime Minister Kazimierz Marcinkiewicz appeared to pin his hopes on Germany, the largest contributor to the EU's funds, to block Mr Blair.
"I hope that Germany will not back the idea of developing the EU at the cost of a reduction in funds, and especially not structural funds for new members," he said.
Leaders of the Baltic states also lined up to attack the proposals.
Estonian Prime Minister Andrus Ansip said that in the EU, rich countries had to help the poor, and he called on the UK leader to show "solidarity" with smaller nations.
Latvian Prime Minister Aigars Kalvitis said none of the 10 new EU member states would accept a deal that harmed countries which needed support for their development.
Lithuania's Algirdas Brazauskas said the British proposal would cost his country 600 million euros (£400m; $700m).
According to the Reuters news agency, leaders of nine of the 10 countries have signed a letter to Mr Blair which states: "We will not be prepared to accept reductions in allocations for the new member states."
The agency says the one country that has not signed the letter is Slovakia, to which the UK has reportedly promised extra funds for decommissioning nuclear power stations.
The UK proposal will be discussed by EU foreign ministers on 7 December, and by heads of state and government at a summit in Brussels on 15 and 16 December - two weeks before the UK ends its presidency.
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