(ANSA) - Vatican City, December 17 - Pope Benedict XVI on Thursday made a last-ditch appeal to world leaders to put the good of the planet above national interests, as the United Nations climate change summit neared its end.

Gruelling negotiations ground to a near standstill as the two-week conference moved into its final 24 hours but the pope suggested an agreement was still possible.

''More decisive commitments are now needed both at an individual and a collective level,'' he said.

''The political and diplomatic decisions at stake in addressing the complex issue of climate change will be a testing ground for countries willing to overcome short-term national interests in favour of long-term benefits for the entire human race''. He urged leaders to be positive about proposals ''in order to reach binding international agreements that are vital to everyone and fair to everyone''. Benedict said it was important to acknowledge industrialized states bore the ''historical responsibility'' for the present ecological crisis and urged them to adopt a ''profound, long-term review of our model of development''.

Over 120 leaders from around the world are expected in Copenhagen for the conference's final day but expectations of an agreement have almost vanished.

Many longstanding sticking points have yet to be resolved and new sources of disagreement have arisen since the conference got under way on December 7.

Developing countries, including China, want industrialized states to renew their binding commitments under the Kyoto protocol, the first stage of which is set to expire in 2012. They blame the crisis on industrialized states, which they say should provide financial support to help them cope with climate change and mitigate their economic losses if forced to curb emissions. Although the European Union has pledged seven billion euros and Japan over ten billion euros for the 2010-2012 period, emerging states say this is not nearly enough and have also called for funds to be provided in direct aid rather than through alternative schemes, such as carbon trading. Developed nations have pledged to try cap emissions at a level that will ensure a temperature rise of no more than 2C above pre-industrial levels by 2050 but island states say that will be too late and want a 1.5C target instead. There has also been disagreement about whether to extend the Kyoto protocol and produce a separate accord for non-signatories, chiefly developing countries and the United States, or whether to merge the existing protocol into a single new agreement for everyone. Japan, the US and the EU back the latter proposal but developing states believe Kyoto members are trying to wriggle out of its tough restrictions.

Meanwhile, arguments between high-emitting states have focused on the level of cuts and the nature of any commitments. The US has said it will not accept binding restrictions unless China does the same, while EU negotiators are frustrated with both countries. On Thursday, Italian Environment Minister Stefania Prestigiacomo recalled the EU had promised to raise its target of a 20% cut in emissions levels on 1990 by 2020 if others agreed to similar restrictions. ''Without binding commitments from the US and China, Europe agreeing to increase its target from 20% to 30% would have no impact either on the negotiations or on the climate,'' she said.

She recalled that the US and China alone are responsible for 50% of global greenhouse gas emissions. ''Without them, a climate agreement is meaningless,'' she added. ''Europe will continue to work towards a global agreement on the climate but certain pre-conditions are essential,'' the Italian minister continued.

''The US must set emissions-cutting targets comparable to European ones, and emerging countries must assume binding commitments to limit their emissions''. Talks at Copenhagen ground to a complete standstill on both Monday and Wednesday, as a result of anger over last-minute draft texts produced by the Danish hosts of the summit, which developing nations viewed as an effort to sideline them and jettison the Kyoto protocol. The Executive Secretary of the UN Framework Convention on Climate Chang Yvo de Boer said that working groups would report back late Thursday on two negotiating texts.

One group was looking at extending emissions cuts under the existing Kyoto protocol, while the other was considering an agreement committing all nations to fighting climate change.

Environment ministers from most of the 190 countries participating in the talks are scheduled to continue working through the night in hopes of a last-minute agreement for leaders to sign on Friday.