Greta Thunberg looked unimpressed today as she watched EU chiefs unveil a new climate law which she has already dismissed as 'surrender'.

The 17-year-old Swedish activist was the star guest at a European Commission meeting in Brussels today where the new legislation was officially proposed.

Thunberg today questioned the urgency of the commission and said: 'When your house is on fire, you don't wait a few more years to start putting it out. And yet this is what the Commission is proposing today.'

The new law would commit the 27-member bloc to reaching zero greenhouse gas emissions by 2050 and give Brussels new powers to impose emission targets.

But the announcement has already fallen flat with environmental groups after Thunberg and dozens of her fellow activists declared the law inadequate.

Underwhelmed: Climate activist Greta Thunberg (right) with European Commission president Ursula von der Leyen (left) at a meeting of the EU's executive arm today

European Parliament President David Maria Sassoli (right) welcomes Swedish climate activist Greta Thunberg as she arrives at the European Parliament in Brussels today, ahead of the European Union unveiling a landmark law to achieve 'climate neutrality' by 2050

Greta Thunberg is welcomed to the European Parliament by its president, David Sassoli, as she visits Brussels to lobby for climate change action today

Thunberg sat alongside Commission president Ursula von der Leyen during the meeting at the body's Brussels headquarters today.

She has also met a committee of MEPs, after an exception was made to a coronavirus-related ban on visitors to the European Parliament.

But she and 33 other youth climate activists have already condemned the EU's climate plans as insufficient in an open letter.

16-year-old Greta Thunberg makes an opening speech of an Environment, Public Health and Food Safety Committee meeting held at European Parliament in Brussels today

Greta Thunberg addresses the environment committee at the European Parliament in Brussels today

Greta Thunberg is pictured after arriving at European Parliament in Brussels today for a meeting to urge the EU to be more ambitious ahead of unveiling plans to be carbon neutral by 2050

'Net zero emissions by 2050 for the EU equals surrender. It means giving up,' the letter said.

'We don't just need goals for just 2030 or 2050. We, above all, need them for 2020 and every following month and year to come,' it said.

Speaking to the MEP committee, Thunberg said: 'Here you are, trying to create laws and policies once again ignoring it. Pretending that your plan or policy disregarding the united science will somehow solve the biggest crisis humanity has ever faced.

'The European Union must stop 'pretending that you can be a climate leader and still go on building and subsidising new fossil fuel infrastructure.

Greta Thunberg speaks to the press after the meeting in Brussels earlier today

The 17-year-old Swedish climate activist sits at the meeting at EU headquarters in Brussels today where she watched EU chiefs unveil a law she has already declared inadequate

Death stare: Greta Thunberg's unamused facial expression previously became a meme after she glared at Donald Trump at a United Nations summit last September

'We will not be satisfied with anything less than a science-based pathway which gives us the best possible chance to safeguard the future living conditions for humanity and life on earth as we know it,' Thunberg said.

She also added that children had been 'sacrificing' their education for the cause for a year and a half.

Thunberg's unamused facial expression previously became a meme after she glared at Donald Trump at a United Nations summit last September.

At the same event, she memorably tore into world leaders for their inaction on climate change, asking them repeatedly: 'How dare you?'.

Thunberg made an impassioned address on stage at the UN last September (pictured), tearing into world leaders for their inaction on climate change

Ursula von der Leyen, the German former defence minister who became European Commission chief last year, speaks to Thunberg in Brussels today

Thunberg arrives for the meeting today with Ursula von der Leyen and other EU officials including Commission vice-president Frans Timmermans (left)

Handing more power to the commission, the EU's executive arm, faces almost certain opposition from national governments and the European Parliament.

'Member states and parliament will hate it,' said Quentin Genard of climate think tank E3G in a blog post.

'Even the more pro-European and pro-climate action countries want to keep oversight over climate policies.'

The goal of climate neutrality was approved by EU leaders at a rocky summit in June with coal-dependent Poland the only holdout.

The commission, which proposes EU law, has hailed the draft has the cornerstone of a European Green New Deal that also envisages a major investment drive to decarbonise the European economy.

Greta Thunberg stands before a packed audience of Environment, Public Health and Food Safety Committee members at the European Parliament in Brussels today

Greta Thunberg addresses the environment committee at the European Parliament in Brussels today

Greta Thunberg chats with the media after her speech in Brussels today. Greta is in the Belgian capital for a protest on Friday

Critics say the 2050 goal depends too deeply on technology that does not exist and creates a false hope that climate change can be fixed without fundamentally changing the economy or human behaviour.

Also angering activists, the proposal steps back from the commission's original ambition to order countries to cut emissions by 50 per cent or even 55 per cent from 1990 levels by the end of this decade.

Instead, the EU draft accepts that the existing goal to reduce pollution by at least 40 percent by 2030 will be revised by September.

Ursula von der Leyen gets up from her seat during the Commission meeting today while Greta Thunberg stays sat down to her left

European Parliament president David Maria Sassoli offers a handshake to Greta Thunberg

That is only two months before the UN climate summit in November, when all parties to the Paris Agreement must make more ambitious pledges to put the world on track to limit global warming to 2.7F (1.5C).

Twelve EU countries - including France, Italy and the Netherlands but not the EU's biggest emitter, Germany - want the Commission to revise the 2030 goal in June.

They say that would leave enough time for the EU to adopt the new 2030 target and use it to pressure large emitters such as China to raise their climate pledges before the summit.

'Delaying discussions until September would crush the EU's ability to play a leading role in global climate talks,' Greenpeace climate policy adviser Sebastian Mang said.

Swedish climate activist Greta Thunberg attends a Committee on the Environment, Public Health and Food Safety at the European Parliament in Brussels, Belgium today

The NGO projected an image of flames onto the European Commission building in Brussels on Tuesday, urging leaders to tackle climate change as urgently as if a house were on fire.

Green members of the European Parliament accused von der Leyen of giving up her claim to lead in the global climate debate.

'In the face of Greta, she is breaking her promise to present ambitious climate targets for 2030,' Green lawmaker Michael Bloss said.