If CIA Director John Ratcliffe’s secret trip to Moscow was intended to calm fears of a confrontation between Russia and NATO, it appears to have achieved almost the opposite.

His sudden arrival in the Russian capital this week triggered days of speculation over what intelligence could have prompted Washington to dispatch its spy chief to deliver a message to Moscow and whether the Baltic states should be worried.

US media reported that Ratcliffe warned Russia against attacking NATO members, particularly Estonia, Latvia and Lithuania, amid intelligence assessments that Moscow could seek to test the alliance as its war in Ukraine remains deadlocked.

American thinktank the Institute for the Study of War (ISW) said the circumstances of the visit suggest Washington regarded the intelligence behind it as sufficiently urgent and sensitive to justify Ratcliffe travelling to Moscow in person.

“US Central Intelligence Agency Director John Ratcliffe’s visit to Moscow suggests that Russia may be preparing to conduct an act of aggression against a NATO member in the relatively near term to invalidate NATO’s Article 5,” ISW said.