According to Jovita Neliupsiene, the environment commissioner will be having to oversee the implementation of EU legislation and represent the bloc in negotiations with third countries.

"We are not aware of and do not see much of the hard work that is done by the commissioner responsible for environmental protection, waste disposal, cleaning, and implementing the directives and regulations that the EU adopts," the ambassador told reporters in Brussels.

"We do not see that day-to-day work with member states to oversee and ensure that all of us understand the regulations and directives we are adopting," Neliupsiene said.

"Another area of huge responsibility, which we sometimes may not notice but which is visible from an international perspective, is to speak to third countries, non-EU countries, to make the world a cleaner, more sustainable, healthier place," she added.

According to Neliupsiene, Sinkevicius will also have to deal with issues related to the Baltic Sea, such as pollution, intensive shipping and fishing quotas.

Sinkevicius has been handed the environment and oceans portfolio in the new European Commission. However, Frans Timmermans, an influential Dutch politician, has been put in charge of the climate change agenda, and will have the final say on how much responsibility the Lithuanian commissioner will be given.

On Thursday, Sinkevicius will have to go through a three-hour long hearing in front of the European Parliament. He will have to respond to 25 questions related to the portfolio he has been assigned.

The Environment, Public Health and Food Safety Committee, and the Fisheries Committee are in charge of the hearing.