The presumed death of Wagner chief Yevgeny Prigozhin is another sign that Russia's governance is "starting to crack", the Ukraine's head of mission to the European Union, Vsevolod Chentsov, told The National on Thursday.
"The more turbulence, the more uncertainty, the more challenges that the Russian regime faces, the easier [it is] for Ukraine to survive the fight," Mr Chentsov said on the sidelines of an event to celebrate Ukraine's Independence Day in the Belgian town of Grimbergen, north of Brussels.
The crash occurred two months to the day since Prigozhin led an abortive mutiny against the army top brass, accusing them of incompetence in their handling of Russia's war in Ukraine.
Russian President Vladimir Putin at the time accused the leaders of the failed mutiny of treason.
Belarus President Alexander Lukaschenko then claimed to have brokered a ceasefire that involved Prigozhin leaving Russia for Belarus, but the mercenary leader was then seen in public at an Africa summit last month in Moscow.
Earlier this week, he broadcast a video of himself in military gear claiming to be in an unspecified country in Africa.
Mr Putin has stayed silent since news of Prigozhin's presumed death started circulating, although he has pointed the finger at Ukraine, a claim rejected by Kyiv.
Western officials and experts on Russia say they believe the Kremlin was involved in the plane crash.
Mr Chentsov cautioned against believing reports in Russian media about Prigozhin's death without further proof.
Yevgeny Prigozhin reportedly killed in plane crash - video
"Do you believe Russian media? They can say anything," he said. "I need to see a [death] certificate.
"Whether he's dead or alive, what is happening in Russia shows that the system has started to crack," Mr Chentsov added.
"This war is also a degradation of the Russian system. As any empire about to collapse, it wants more territories. They need war to survive. That is the paradox of empires."
For now, Prigozhin is certainly "out of the game", according to Mr Chentsov.
"The Wagner group did a lot of bad things on the battlefield," he said. "It's a good development."
The Wagner group, a mercenary force founded in 2014, which is also active in the Middle East and Africa, played a key role in helping Moscow capture the Ukrainian city of Bakhmut in May 2023.
Wagner chief Prigozhin presumed dead in plane crash - in pictures
Yet some countries, particularly in Eastern Europe, have expressed fears of a worsening of tensions in the region after Progozhin's death.
Lithuania's President Gitanas Nauseda on Thursday said that Prigozhin's death does not improve regional security.
"We really shouldn't think that Prigozhin's death makes us feel calmer or that it somehow improves the security situation," Mr Nauseda said.
In similar remarks on Thursday, Polish Prime Minister Mateusz Morawiecki said the Wagner group was now "under direct supervision of Putin and his people".
"Even more than before, or at least to the same extent as today, it will be used as a tool of provocation, blackmail ... to destabilise countries bordering Russia and Belarus," Mr Morawiecki said.
Both Vilnius and Warsaw had previously suggested that Wagner mercenaries could help facilitate illegal migration from Belarus or even enter the countries disguised as irregular migrants.
Last week, Lithuania closed two of its six border checkpoints with Belarus.
Images obtained on Wednesday by US media organisation Radio Free Europe/Radio Liberty show that a camp suspected to be occupied by thousands of Wagner group fighters in Belarus was being dismantled.
The images show that the process of dismantling the camp started on August 1. The news website said that the change affected housing and not military equipment.