The EU must keep costs and spending "under control", David Cameron has told European Council president Herman van Rompuy, as they met for talks amid wrangling over future Brussels budgets.
The Prime Minister has threatened to veto any long-term spending increase above inflation - effectively a real-terms spending freeze for the EU budget.
And Downing Street has dismissed a separate inflation-busting rise in EU spending approved by MEPs as "completely unacceptable".
Welcoming Mr von Rompuy to Downing Street, Mr Cameron said there were "very big issues to discuss at the moment in the European Union".
He said he was sure the question of the budget - due to be discussed by leaders at a summit next month - would be among these issues, as well as "how important I think it is that we keep our costs and our spending under control".
Other items on the agenda for the talks were promoting growth across the EU and the need for it to take a "strong stance in the world" on issues such as Syria and Iran, Mr Cameron said, as the two sat down in Number 10.
The European Parliament this week backed a 6.8% rise in EU spending for 2013 and an overall rise of at least 5% for 2014/20, both due to be agreed before the end of the year.
The long-term budget requires unanimity among the 27 member states, giving the UK a veto when national government leaders gather for a special European Council summit next month.
But the budget for the single year 2013 is decided by qualified majority voting, meaning Britain could be over-ruled.