New European Commission chief Jean-Claude Juncker has said the body is "thinking about a solution" to the EU budget contributions row that followed the recent European Council summit.

A number of EU leaders have voiced opposition to demands from the Commission to pay large top-up payments to the EU budget by the start of December, with UK Prime Minister David Cameron refusing to pay the requested sum by the deadline.

Mr Juncker was speaking during an "open conference of presidents" meeting with MEPs on 4 November 2014, to debate the results of the meeting of EU leaders in Brussels on 23-24 October.

European Council President Herman van Rompuy, speaking in front of MEPs for the last time before he is due to leave office next month, defended climate change targets agreed at the summit as a combination of "ambition and realism".

EU leaders agreed a nationally binding target to cut greenhouse gas emissions by 40% below 1990 levels by the year 2030, as well non-binding targets to increase energy efficiency and use of renewable energy across Europe.

The targets were welcomed by Conservative group leader Syed Kammall, although he said they would be "meaningless" unless large polluter countries such as the United States and China agreed also agreed to more ambitious targets in the near future.

A number of other MEPs, however, were more lukewarm in their response, with Belgian MEP Philippe Lamberts, who co-chairs the Parliament's Green group, saying the aspirations would be "insufficient" to meet the stated environmental ambitions.