‘If Ukraine fails, war will come to the streets of European cities,’ former foreign minister says

"Putin today has no strengths and powers to fight multiple wars," Kuleba said, pointing to the recent fall of Russian-backed Bashar al-Assad's regime in Syria as an example. He does however have "resources to fight one war per time," meaning if Ukraine falls, Europe will be next in the Russian president's line of sight, Kuleba warned.

Former Ukrainian Foreign Minister Dmytro Kuleba warned of the potential repercussions for the European Union if Ukraine does not prevail in its fight against Russia, telling CNBC that "if Ukraine fails, war will come to the streets of European cities."

On NATO membership — a guarantee Ukraine has been chasing for years — Kuleba called it a necessary step in preventing a future resurgence of the conflict with Russia. "Putting membership in NATO for Ukraine on hold can theoretically help end the fighting and establish a ceasefire," he said, "but it will not prevent the second Russia-Ukraine war from happening."

A view of the destruction resulting from a Russian attack in Kostiantynivka, Ukraine on November 21, 2024. Diego Herrera | Anadolu | Getty Images

Security guarantees as an alternative to membership are not enough, Kuleba added, saying that most of the proposals have already been granted to Ukraine as part of commitments signed with multiple countries including the U.K. The former minister was confident that when "serious people" sit down to discuss the prospect of Ukraine joining the alliance, they would realize it was the only way forward. The issue of Ukraine's NATO membership has been fraught and sensitive for several of the organization's members, whose approval is unanimously required to accept a new member state.

With President-elect Donald Trump set to make his return to the White House in January, Kuleba said it remains to be seen what specific policies he will implement, calling recent talks between Zelenskyy and Trump "a good sign." The two leaders met in Paris along with French President Emmanuel Macron ahead of the reopening of the Notre Dame Cathedral. After his meeting with the Ukrainian President, Trump called for an "immediate ceasefire" in the almost three-year-old war.

Minister of Foreign Affairs of Ukraine Dmytro Kuleba attends a joint briefing with Minister of Foreign Affairs of the Netherlands Hanke Bruins Slot. Future Publishing | Getty Images

Donald Trump previously claimed on the campaign trail that if elected, he could end the war "in 24 hours." Kuleba, meanwhile, stressed that the "key to peace" is in Moscow rather than Kyiv. The former foreign minister said Trump's primary focus should be on how to make Russian President Vladimir Putin negotiate in good faith. On potential terms of a peace deal, Kuleba said President Zelenskyy will be doing "everything he can in order not to allow any peace settlement to come at the expense of Ukraine" – and that no political leader in Ukraine could ever allow the ceding of territory as it goes against the country's constitution.