He cited Croatia as an example.
The full reintegration of Russia-occupied territories in eastern Ukraine, Donbas, may take at least a quarter of a century.
Ukraine's Deputy Prime Minister for Reintegration of Temporarily Occupied Territories Oleksiy Reznikov gave this forecast in an interview for the Dzerkalo Tyzhnia (Mirror Weekly) publication.
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"Yes, I continue to insist that the full-fledged reintegration could take at least 25 years, at least one generation. This is my belief," he said.
He cited the example of Croatia, where the war ended 25 years ago but in particular, a mine clearance effort will last until 2026.
"When the [Russian] occupation ends one way or another, we will continue to work with the [local] population so that those territories fully enter the legal field of Ukraine, and most importantly, its mindset field," he said.
He also says that statements that it is possible to reintegrate the currently occupied territories within a year or two are made "because of misunderstanding." "Yes, it is [only] possible to restore the constitutional order," he added.