The European Parliament is debating a motion that would declare a "climate emergency", just a week before the United Nations climate conference in Madrid.
Lawmakers who backed the declaration said it would increase pressure on the new incoming EU Commission starting on December 1.
They plan to pass the symbolic declaration during a debate on the United Nations' COP25 climate summit, which begins December 2 in Madrid.
Liberal MEP Pascal Canfin, chair of the Environment committee of the European Parliament is one of the MEPs leading on parliament's resolution ahead of the U.N summit.
"Europe's declaration of a state of climatic and environmental emergency is symbolic. But if we do not vote in favour on Thursday, then the symbolism would be terrible. I appeal to the responsibility of each Member of the European Parliament", Canfin said on Twitter.
However, the declaration has drawn criticism from environmental activists and organisations, that demand further action to tackle the climate emergency.
"The world is not asking for "symbolic" acts. We need real and courageous decision making to handle the Climate Emergency", Greenpeace tweeted.
Green MEP Ville Niinisto told Euronews that two resolutions are proposed: "One resolution is about declaring a climate emergency but also increasing the pressure that the parliament puts on the Commission and member states to increase targets and decarbonisation rates."
"But in our resolution, we push for Europe's decarbonisation by 2050. The liberals have a proposal that is just a formal declaration of emergency".
The parliament has repeatedly pressed the European Commission to take a stronger stance on climate change.
The incoming president of the Commission, Ursula von der Leyen, has said combating climate change will be one of her top priorities.
She wants a "European Green Deal" intended to achieve carbon neutrality with net-zero emissions by 2050.
Current targets aim to cut the EU's greenhouse gas emissions by 40% by 2030 from 1990 levels. Von der Leyen hopes to raise the goal to at least 50%.
All but three of the EU's 28 member states have signed up to this objective, but objections from Poland, Hungary and the Czech Republic prevented the bloc promoting its stance at a U.N. climate action summit in September.
Several countries, regions and organisations have symbolically declared a "climate emergency" to emphasise the urgency of the issue.