European capitals are debating new collective ways to respond to Russian acts of aggression below the level of an armed attack, as some fear existing mechanisms are failing to deter Moscow's so-called hybrid war. Countries are split over how to confront the Kremlin's acts of sabotage, arson and destabilisation, but a growing number are seeking collective processes for punishing Russia over attacks that do not meet NATO's benchmark to trigger its Article 5 mutual defence clause.

"If we are facing hybrid warfare, we need to have hybrid defence," said Andrius Kubilius, the EU's defence commissioner. "That's very clear . . . We shall look at how to define what means we need to be ready to use."

EU defence ministers will gather in Brussels today to discuss a proposal from the European Commission to create a new Emergency Security Protocol that could be triggered when countries are hit by such attacks, to co-ordinate effective responses. This would resemble discussions triggered by NATO's Article 4 if an ally feels their "security is threatened". Article 4 has been invoked nine times in NATO's history, including twice last year. Henry Foy has the story.

In other news, the US and China have agreed to create a lower tariff regime covering $60bn in trade, UK chancellor John Healey will announce a £6bn naval plan, and Pope Leo XIV visits the hometown of EU founding father Robert Schuman.