"I welcome the constructive proposal made by France and Germany," said Von der Leyen who is head of the European Commission, the EU's executive arm that would implement the plan.
"It acknowledges the scope and the size of the economic challenge that Europe faces," she said.
"This goes in the direction of the proposal the commission is working on which will also take into account the views of all member states and the European Parliament," Von der Leyen said.
The joint stance by France and Germany is significant as it will put pressure on the EU's more frugal minded member states to contribute the extra money needed to pay for the plan.
The 500 billion euros ($545 billion) will come in addition to the EU's normal spending plans for 2021 through 2027, which are currently under negotiation.
Europe has seen some of the worst effects of the pandemic, with highly indebted countries such as Italy and Spain calling for help from richer partners such as Germany and the Netherlands.
Those countries are reluctant to get into a major borrowing scheme with their southern partners that are seen as overspending and reluctant to implement necessary economic reforms.
"It is going to take willingness to reach an agreement and everyone is going to have to shift their positions," a European official said on condition of anonymity.
The latest statements by German Chancellor Angela Merkel "will help", the source added.