The 27-nation bloc had already financed arms purchases to help Kyiv fight Russia's invasion, but outside its budget, thanks to an ad hoc financial instrument.

"This is the first time we use EU budget to support Member States in commonly procuring defence products," said European Commission vice-president Margrethe Vestager.

The bloc was investing 300 million euros ($317 million) in to support groups of up to nine member countries buy air defence systems, armoured vehicles and artillery ammunition, the commission said.

"Importantly, the selected projects will also increase our support to Ukraine, with additional defence equipment," Vestager said.

Since Russia's invasion in February 2022, the EU has been working to boost its defence industry to arm Ukraine and build up its own forces.

It set up a financial aid mechanism aimed at encouraging the purchase of ammunition by member states, but fell short of a promise made last year to supply Kyiv with a million artillery shells by the end of March.

EU diplomacy chief Josep Borrell has vowed the goal will be reached before the end of the year.