In an interview with Euronews, EU's top job candidate Frans Timmermans made the case for a CO2 tax at the European level.
The social democrat was taking a question about the ways to finance climate change policies.
"That is the biggest change that will lead to polluters understanding they need to change the way they produce," he said.
"What we also need to do is to make sure that carbon trading goes up by lifting the price of that," Timmermans continued, arguing the EU should follow the example of plastic waste.
"What we introduced for instance in the plastics legislation is that producers are also made responsible for the waste they create so if you can't reuse or recycle and it becomes waste then the costs will increase and that's how you make producers responsible for the waste they create," Timmermans said.
Timmermans is among those hoping to succeed Jean-Claude Juncker as president of the European Commission after May’s elections.
Euronews is hosting a series of interviews with candidates from across the political spectrum.
On Thursday (April 25), Euronews spoke to Green candidate Ska Keller. Coming up next are Violeta Tomic, candidate of the Left (April 30), Guy Verhofstadt, representing the Liberals (May 13) and Jan Zahradil from the Conservatives (May 14).