David Cameron will return to Brussels on Tuesday in an official capacity for the first time since his doomed campaign for Britain to remain in the European Union. The former prime minister, who made a surprise return to frontline politics this month when he became the UK foreign secretary, will attend a Nato meeting of foreign ministers to discuss issues including ammunition supply to Ukraine and the alliance’s continued presence in Kosovo. He is also expected to try to squeeze in a meeting with Maroš Šefčovič, the vice-president of the European Commission responsible for the Brexit deals, before or after the two-day summit. Referring to the tortuous years-long negotiations surrounding the UK’s departure from the EU in 2020, one diplomat likened Cameron’s visit to the EU headquarters to a “divorcee returning to the family home”. But though his history with Brussels has had its complications, Cameron’s return to politics after a reshuffle by Rishi Sunak has caused a frisson of anticipation around the Nato table. “Everyone, I mean everyone, is looking for bilaterals with him,” said one source. At Nato, Cameron is expected to brief fellow foreign ministers on his recent trip to Kyiv, with a tough conversation expected on the implications of Donald Trump’s possible return to the White House next year. If he does meet Šefčovič – a man who, according to a senior diplomat, used to refer to his meetings with the UK’s chief Brexit negotiator, David Frost, as his “weekly root canal appointments” – Cameron is likely to discuss a looming 10% tariff on electric vehicle exports that was written into the Brexit deal negotiated by Boris Johnson’s team. Germany and the UK car manufacturing sector have been lobbying hard for the tariff to be suspended for three years. But France has been holding out, arguing any change to the divorce deal, even to its annexe, constitutes a reopening of the entire agreement. That would then need signoff by prime ministers across the EU, many of whom have no interest in the issue. The Nato secretary general, Jens Stoltenberg, said on Monday western allies had no alternative but to keep backing Ukraine’s fight against Russia, in the face of doubts over US support to Kyiv. He said: “It very often happens in wars that when people realise that this may last a long time, of course, that is demanding, that is difficult. “We don’t have any alternative. The alternative, to let President [Vladimir] Putin win, is a tragedy for Ukraine and is dangerous for us.” The US had provided more than $70bn (£55bn) to Ukraine since Russia’s invasion, the second biggest contributor after the EU, which had provided about €100bn (£87bn), said James O’Brien, the US assistant secretary for European and Eurasian affairs, in a separate briefing to reporters. But opposition from hardline Republicans has thrown into question the future of US assistance. “Despite the difficulties, despite the lack of progress or achievements or territorial gains, we need to continue to support Ukraine,” Stoltenberg said. Ukraine’s foreign minister, Dmytro Kuleba, will also address the ministers as part of the first meeting of the Nato-Ukraine Council. “In that session, they will have the opportunity to reaffirm the alliance’s steadfast commitment to Ukraine,” said O’Brien. “This is really a coalition effort, and I think it’s important for our partners to hear that we’ll continue to do our part, even while our Congress is debating the next steps of what we’ll provide.”