The writer is director of the Carnegie Russia Eurasia Center in Berlin

With yet another in-person summit between Donald Trump and Vladimir Putin in the works, the war in Ukraine is reaching a new inflection point. The Kremlin is also signalling that it is more willing to generate risks and costs for Europe now that the continent provides the main lifeline for Kyiv’s self-defence. As Europe scrambles to deter Russian belligerence, there is one instrument glaringly absent from its toolkit: discreet channels of communication with the adversary.

Since February 2022, the west has seen several critical moments that could have spiralled into a direct confrontation between Russia and Nato. At every turn, the coalition used channels of communication to the Kremlin for risk management. Constant and discreet channels between seasoned US national security professionals and their Russian counterparts were always there to ensure that any Nato step to elevate support for Ukraine would be backed up by conflict diplomacy.