Oleksandr Usyk has been released after being detained in Poland on Tuesday night.
A video emerged on social media of the heavyweight champion in handcuffs at Krakow airport.
The reasons for his detention remain unclear but Usyk took to Instagram to say it was “a misunderstanding” with local police.
He wrote: “Dear friends, a misunderstanding took place.
“It was quickly resolved. Thanks to all who got concerned.
“Thanks to Ukrainian diplomats for the efficient support.
“And respect to Polish Police for conducting their obligations with no regards to height, weight, reach and regalia.
“Thanks God to everything.”
Sky Sports News has reached out to Usyk’s management for further clarification on the circumstances.
Ukraine president Volodymyr Zelenskyy said on Telegram: “I spoke to Oleksandr Usyk on the phone when he was detained.
“I was outraged by this attitude towards our citizen and champion.
“I instructed the Minister of Foreign Affairs of Ukraine Andriy Sybizi and the Minister of Internal Affairs of Ukraine Ihor Klymenko to immediately investigate all the details of the incident at the Krakow airport.
“As soon as I was informed that everything was fine, our champion was released and no one else detained him.”
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