French President Emmanuel Macron has been pushing for the 27-nation union to develop more autonomous military capacities alongside the Western alliance.

And the rapid collapse of Afghanistan's government at the end of the 20-year-old US-led mission in Afghanistan has intensified debate in Brussels' about the EU's role.

"It is time for Europe to step up to the next level," von der Leyen told the European Parliament in her annual State of the European Union address.

"President Macron and I will convene a summit on European defence," she said.

France will take over the six-month rotating presidency of the union at the New Year, and Macron will push for member states to commit to more defence coordination.

But most EU nations are also members of the NATO alliance and some, particularly eastern states more exposed to the threat of Russia, do not want to undermine ties with the United States.

"Witnessing events unfold in Afghanistan was profoundly painful for the families and friends of fallen servicemen and servicewomen," von der Leyen said.

"We have to reflect on how this mission could end so abruptly. There are deeply troubling questions that allies will have to tackle within NATO.

"But there's simply no security and defence issue where less cooperation is the answer."

Von der Leyen vowed to work with NATO Secretary General Jens Stoltenberg on a new EU-NATO joint declaration to be presented before the end of the year.

"But this is only one part of the equation," she said. "Europe can and clearly should be able and willing to do more on its own."