Brussels - EU leaders have said they will decide on a more stringent climate target for 2030 at a summit in December, leaving more time to forge a united response to climate change.
Ambitious climate goals are backed by big EU powers including France and Germany, as well as many major businesses, but face resistance from eastern member states still dependent on coal for energy.
The 27 leaders meeting in Brussels said they will return to the issue "with the aim of agreeing on a new emission reduction target for 2030", conclusions from the summit said on October 15.
As part of its commitments to Paris Climate Agreement, the EU has pledged to being climate-neutral by 2050 when it would offset or capture more greenhouse gas than it emits.
EU CO2 emissions in 2019
However, the current interim target for 2030 -- a 40 percent reduction in CO2 emissions compared to 1990 -- is not sufficient to achieve the goal.
The European Commission, the EU's executive arm, has therefore proposed a target of at least 55 percent, while the European Parliament has gone even further with 60 percent.
Germany, which hold the rotating EU presidency, decided to postpone a possible agreement to the summit on December 10.
Eleven countries, including France, Spain and the Netherlands, expressed their support for a reduction of "at least 55 percent" in a joint letter on Wednesday.
But several Eastern European countries are opposed, including Poland, which is still heavily dependent on coal and refuses to commit to carbon neutrality.
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"If it's a median target for the EU as a whole, there's no problem -- some countries could reduce (their emissions) more. But we, the Czech Republic, will not achieve it," Czech prime minister Andrej Babis said on Thursday.
Bulgarian Prime Minister Boiko Borissov pointed to the economic cost to his country's mining sector: "Our preliminary calculations suggest that a 40 percent cut is a ceiling," he warned.
The holdout states are expected to ask for additional funding, through something called the EU Just Transition Fund.
"All member states will participate in this effort, taking into account national circumstances and considerations of fairness and solidarity," the summit's conclusions said.
Climate change scenarios