German Defence Minister Boris Pistorius said on Thursday that Russia would be remain a threat to Europe's security even if an agreement for peace in Ukraine can be reached.

"It would be naive to believe that this threat, even after any peace agreement whenever it materialises, would in fact subside," Pistorius said ahead of a meeting of NATO defence ministers in Brussels.

"That's why we have to invest faster and more in our defence and security capabilities. Peace, this has unfortunately been the experience over centuries, can only be secured from a position of strength," he added.