Germany's constitutional court on Wednesday allowed the approval of legislation ratifying the European Union's Recovery Fund as it dismissed legal challenges against the debt-financed investment plan.

The decision is essential for launching the bloc's 750 billion euro ($900 billion) recovery spending plan to mitigate the consequences of the COVID-19 pandemic measures.

"The drawbacks resulting from not approving the provisional measure and the law later turning out to be unconstitutional are smaller than the consequences of approving the measure and the constitutional challenge later turning out to be unfounded," the court said in a statement.

The change that is to be ratified raises the upper limit for national contributions to the EU budget by 0.6 percentage points to 2.0% of gross national income until 2058 to safeguard the repayment of the recovery borrowing in case there is not enough money from taxes planned for that purpose.

Seven out of the eight judges supported the decision, the court said.

Germany's top court had issued an injunction in March against the signing off on the EU law by the German president because of an emergency appeal against it from the far-right Alternative for Germany (AfD) party and a group called Citizens' Will Alliance.