EU countries have unlocked some 5.6 billion euros in common funding to help arm Ukraine in its fight against Russia since Moscow invaded last February.

The bloc's member states recently signed off on using two billion euros for a plan aimed at getting one million artillery shells to Ukraine over the next year.

That means the bulk of the nearly eight billion euros currently allocated to the joint European Peace Facility (EPF) has already gone towards Ukraine.

Budapest -- which has the closest ties in the EU to Russia -- says it is opposing a new disbursement as the funds were meant to support partners around the world, not just Ukraine.

"The Hungarian government does not agree that the European Union -- having other instruments at its disposal -- should use the European Peace Facility exclusively for Ukraine," the Hungarian government told AFP on Tuesday.

"It is crucial for the Hungarian government that these issues are clarified, which is why it has not approved the disbursement of yet another tranche of the European Peace Facility."

Several European diplomats confirmed Wednesday that Hungary was stalling the new chunk of funds to reimburse EU countries for the cost of weapons sent to Ukraine.

Diplomats were still seeking to get an agreement for a meeting of EU foreign ministers in Brussels on Monday, they said.

The debate over the funding comes as Ukraine is desperately pleading for weaponry for its forces as they gear up for a counter-offensive.

The EU's member states agreed last year that they could in principle raise the ceiling of the EPF by another 3.5 billion euros to help see it through to 2027.