The EU unveiled national targets Wednesday for cutting greenhouse gases by 2030, insisting Britain is still legally required to help the bloc meet its UN goal despite being set to leave.

Wealthy northern European countries including Britain bear the brunt of the EU's plans to meet the commitment it made at the Paris climate summit in December to cut emissions by 40 percent over 1990 levels.

Despite Britain's shock referendum vote last month for Brexit, the European Commission included it on its list of proposed binding emissions targets for all 28 EU countries.

"These targets are realistic, fair and flexible," EU Climate Commissioner Miguel Arias Canete told a press conference, adding that the targets would become legally binding if and when approved by member states.

Under the targets, which are based on economic growth, Sweden and tiny Luxembourg must cut emissions by 40 percent over 2005 levels, while Finland and Denmark must cut emissions by 39 percent and powerhouse Germany by 38 percent.

Britain and France are asked to cut emissions by 37 percent while Netherlands and Austria should cut by 36 percent.

"Let's be very clear: from a legal point of view the outcome of the referendum has not changed anything," Spain's Canete said when asked whether the proposed targets would have to be readjusted following Britain's exit.

"The UK (United Kingdom) remains a member state with all the rights and obligations for member states and EU law continues to apply in full to the UK," he said.

New British Prime Minister Theresa May's government has yet to initiate the exit negotiations but has promised to follow through with the process that could take several years.

- 'Astoundingly out-of-synch' -

In contrast, poorer eastern and southern EU countries are asked to contribute far less to the targets, despite the fact that they often rely more heavily on dirtier fossil fuels.

Bulgaria, the poorest state in the bloc, was given an emissions reductions target of zero percent, while Romania, Latvia, Croatia, Poland, Hungary and Lithuania are all set below 10 percent.

Poland in particular gets off lightly given its reliance on coal-fired power stations.

Canete added that the targets offer incentives for investment in sectors like transport, agriculture, buildings and waste management.

The system allows for flexibility. Member states can reduce emissions jointly across a range of sectors and over time.

Despite it being denounced as a loophole by environmentalists, they can also transfer cheap carbon credits from the Emissions Trading System, the world's largest, and use forests, which absorb carbon, to count towards their emissions reduction goal.

The ETS puts a cap on carbon dioxide emitted by large factories and other companies, which can trade in quotas of these emissions.

The non-government organisation World Wildlife Fund (WWF) said the proposals fall short of the ambitions Brussels set at the Paris summit, which calls for holding global warming to well under two degrees Celsius (3.6 degrees Fahrenheit).

"Not only is the Commission astoundingly out-of-synch with international climate commitments, but it has also included 'loopholes' in this proposal which will allow countries to cheat their way out of real climate action," said Imke Luebbeke, head of climate and energy at the WWF European Policy Office.

The proposals will be debated by the member states and the European Parliament.