After a week of rushed diplomacy and two major summits over the war in Ukraine, few details have emerged about a key part of a potential peace settlement: security guarantees to help Kyiv fend off any future Russian attacks.

NATO Secretary-General Mark Rutte, who touted the guarantees with other European leaders when they conferred with President Donald Trump at the White House on Monday, was in Ukraine on Friday to lay out a framework to Ukraine’s President Volodymyr Zelenskyy.

“The first layer has to be for Ukrainian armed forces to be as strong as possible to defend this proud country and nation going forward,” Rutte said, saying that would come after a peace deal or “long-term ceasefire.”

He added, “And the second layer has to be the security guarantees provided by Europe and the United States.”