A senior Nato official has apologised and clarified his comments a day after he said publicly that Ukraine could give up territory to Russia in exchange for Nato membership and an end to the war. Stian Jenssen, the chief of staff to the Nato secretary general, Jens Stoltenberg, told a Norwegian newspaper that he should not have spoken as simplistically as he did, after his initial comments prompted an angry reaction from Kyiv. At a panel event in Norway on Tuesday, Jenssen had said that while any peace deal reached would have to be acceptable to Ukraine, alliance members were discussing how the 18-month war might be brought to an end. “I think that a solution could be for Ukraine to give up territory and get Nato membership in return,” Jenssen told his audience, noting that discussions about Ukraine’s postwar status were continuing in diplomatic circles. A day later, he gave an interview to the same newspaper, VG, that had reported on his original comments. “My statement about this was part of a larger discussion about possible future scenarios in Ukraine, and I shouldn’t have said it that way. It was a mistake,” he said. But Jenssen did not walk back the idea that a land-for-Nato-membership deal could ultimately be on the table. If there were serious peace negotiations then the military situation at the time, including who controls what territory, “will necessarily have a decisive influence,” the chief of staff said. “Precisely for this reason, it is crucially important that we support the Ukrainians with what they need,” the official continued as he sought to emphasise that Nato members remained behind Ukraine. Ukraine has consistently called for a restoration of its internationally recognised pre-2014 borders and is engaged in a counteroffensive in an attempt to recapture large parts of its territory seized by Russia. Jenssen was careful in his initial comments to stress that he was simply airing an idea and that “it must be up to Ukraine to decide when and on what terms they want to negotiate”, reflecting Nato’s position that no peace settlement with Ukraine should be agreed without Ukraine. But this was not enough for Kyiv, unhappy that Jenssen, an important figure and close ally of Stoltenberg, was even discussing the proposition in public. Kyiv said any land-for-Nato deal would reward Russian aggression. Mykhailo Podolyak, a senior adviser to Ukraine’s president, Volodymyr Zelenskiy, said: “Trading territory for a Nato umbrella? It is ridiculous. That means deliberately choosing the defeat of democracy, encouraging a global criminal, preserving the Russian regime, destroying international law and passing the war on to other generations.” Podolyak said that unless Russia took a heavy loss in the war, it would continue to pose a long-term problem for the west. “If Putin does not suffer a crushing defeat, the political regime in Russia does not change and war criminals are not punished, the war will definitely return with Russia’s appetite for more.” Ukraine’s position is being tested by the slow progress of its counteroffensive, which began in June. Although Kyiv has received donations of western tanks and long-range rockets and artillery, its forces have so far made only limited territorial gains against heavily defended Russia positions. Nato put out a clarifying statement on Tuesday night aimed at cooling the Jenssen row. “We will continue to support Ukraine as long as necessary, and we are committed to achieving a just and lasting peace. The position of the alliance is clear and has not changed,” a spokesperson said. Discussions about how peace might be achieved are unlikely to subside, particularly given the relative deadlock on the battlefield. “I’m not saying it has to be like this. But that could be a possible solution,” Jenssen said on Tuesday.