The European Investment Bank has pledged to maintain its target of investing around $20bn (£16bn) a year to fight climate change over the next five years.
“We, Europeans, must lead the free world against climate sceptics,” EID president Werner Hoyer said.
He also said Europe must become a leader in funding the next generation of sustainable technologies.
His comments have been seen as a message to US President Donald Trump, who has pledged to scrap the country's strategy to tackle climate change.
He has also suggested he will pull the US out of the Paris Agreement on climate change.
Investment in combating climate change already makes up around a quarter of EIB total loans.
Of the 83bn euros the bank lent last year, 19bn euros went to projects to counter climate change.
"We aim to provide $100bn for climate action over the next five years, the largest contribution of any single multilateral institution," Mr Hoyer added.
Mr Hoyer also said two years of Brexit negotiations would leave the bank's links with the UK in "limbo".
The UK holds 16 per cent of the bank's shares.
“We would be missed in the UK if we had to reduce our business there or disappear completely,” he said
While only EU member states can be EIB shareholders, Mr Hoyer said he did not rule out the possibility of changing the rules to allow Britain to remain a shareholder.
