EU needs emissions deal to avoid 'shame in Bonn'

"It would be a pity if the EU couldn't go to Bonn with this trophy," he added, noting that his centre-right group was "ready to compromise."

Belet spoke to a group of journalists on Tuesday morning, flanked by his EPP colleagues Peter Liese from Germany and Esther de Lange from the Netherlands.

On Wednesday evening, the EU parliament, the Council of the EU - representing national governments - and the European Commission will hold another round of negotiations, known in Brussels as a trilogue.

The legislative proposal was tabled by the commission in July 2015, but can only become law if the parliament and council find agreement.

The proposal deals with how the ETS should be reformed after 2021.

Liese said that if there was no deal, this was not necessarily a legal problem, but a political one.

"Then there will be another trilogue but we will be ashamed in Bonn," he said.

The ETS requires several thousands of industrial emitters in the EU to pay for their CO2 emissions by handing in carbon credits.

The system has been plagued by a glut of allowances and a much-lower-than-expected carbon price, which the reform hopes to resolve.

New modernisation fund

One key point of debate on Wednesday night - and possibly Thursday morning - will be the conditions of a new modernisation fund, which will be used to modernise energy plants in the 10 poorest EU member states.

A contentious point is what projects will be eligible.

Denmark, France, Germany, Luxembourg, Netherlands, Sweden, and the United Kingdom recently signed a letter saying that the fund "should not be used to support any solid fossil fuels-based energy generation".

But Poland would be interested in using the fund to modernise its coal-fired power plants.

German MEP Liese said that Poland "is a big member state" and that it would be good if it was on board on the final agreement, but he also stressed that the Council will vote with a so-called qualified majority, meaning that Poland could be outvoted.

"The modernisation fund is a big thing for Poland, they should not underestimate how much money we transfer from the west to the east, this is substantial," said Liese.

Wednesday's trilogue begins at 6PM.

The ETS price of emitting a tonne of CO2 stood at almost €8 on Monday, much lower than the €20 to €30 that was expected when the system was introduced in 2005.

Environmental campaign group Climate Action Network Europe on Tuesday called on the EU "not [to] bend to the Polish government's demands."

"The Polish government has been running a protracted and bitter campaign to sabotage the integrity of the EU's carbon market. It has put relentless efforts to allow the ETS to subsidise Polish coal plants instead of making them pay for their pollution," the group said in a statement.