European Commission chief Ursula von der Leyen pleaded Wednesday to save her signature "green deal" in the longterm EU budget that has been left short by Brexit.

"If we do not set aside the funds... we will simply fail to achieve a climate-neutral Europe" by 2050 as planned, she told the European Parliament.

Her warning was laid down a week before an extraordinary EU summit in Brussels called to try to find consensus on the bloc's seven-year budget -- the multi-annual financial framework, or MFF, for 2021-2027.

Wrangling over the MFF has become even more fraught because of the gap in contributions caused by Britain's departure from the EU. 

Von der Leyen, the president of the European Commission, told the Strasbourg parliament that the shortfall from Brexit would be around 75 billion euros ($82 billion) over the seven-year period. 

The overall MFF amount is expected to come in at around one trillion euros.

'Frugals' vs 'cohesion'

One group of EU countries known as the "frugal five" -- Austria, Denmark, Germany, the Netherlands and Sweden -- has balked at coughing up more money to cover that gap on top of a list of new spending priorities von der Leyen's Commission wants to promote, including her Green Deal.

A rival group of 16 EU countries, the "friends of cohesion", want more money in the pot so that the EU funding they get to improve their infrastructure, research and administration continues as before.

The European Parliament, which has to sign off on any MFF agreement, is keen for the biggest budget possible, so the EU can meet stated goals to fight climate change, boost defence and security, support migration policy and become a leader in digital industry.

The February 20 Brussels summit is not expected to come up with an agreement but could narrow the differences.

President of the European Council Charles Michel has taken the gamble that he can persuade the leaders of member countries to settle on an MFF before the end of this year. More summits look likely if he is to achieve that.

But it is von der Leyen who has staked the most.

When she took over the EU's executive in December she declared she wanted to helm a powerful European Commission that would be the world leader in achieving carbon neutrality.

She told MEPs: "I for my part will not accept any result that means less than 25 percent of the budget is dedicated to fighting climate change".

"For citizens, this is our top priority," she stressed while recognising that many other demands were also being made on the MFF.