Ursula von der Leyen's second 'state of the union' address since she took over as European Commission president comes after two years that have tested the resilience of the bloc with the COVID-19 pandemic, a sharp economic downturn and strains over Brexit.

"Let's make sure that it does not turn into a pandemic of the non-vaccinated," von der Leyen told EU lawmakers in Strasbourg, France, on Wednesday.

Announcing a new donation of another 200 million doses by the middle of next year, von der Leyen said she was also worried by variation of vaccination rates among the EU's member states.

"The next year will be another test of character," she said.

At the end of August, 70 per cent of the adult population in the 27-nation EU had been fully vaccinated against COVID-19. This marked a milestone after a slow start, but also masked big differences among EU countries.

By mid April, 100 million doses of COVID-19 vaccines had been administered to the EU citizens.

Nineteen EU member states would have their economy back at pre-pandemic level this year, with the others following next year, she said.

Von der Leyen, wore a mask emblazoned with the EU flag's circle of 12 gold stars, greeting lawmakers at the assembly ahead of her speech with fist bumps.

The former German defence minister has put tackling climate change at the top of her agenda, with bold steps for the EU to achieve climate neutrality by 2050, along with a digital transformation of its economy.

Critics say she has fallen short of promises to make the commission more "geopolitical" as the EU struggles to assert its influence in foreign affairs.

Australian Associated Press