Ukrainian boxing champion Wladimir Klitschko said in a recent interview that Russian President Vladimir Putin could set off a third World War. The 38-year old world heavyweight champion said in an interview with sports daily L’Equipe that Putin’s actions in eastern Ukraine could be a precursor to the next World War, reports AFP.

Putin Could Set Off World War 3, Says Ukrainian Boxing Champion

‘In five or 20 years, Putin will apologize’

His remarks came just days after the Russian President revealed in a documentary how he secretly planned the annexation of Crimea. Blaming Western countries for the Ukraine crisis, the leader said Russia was fully prepared to use nuclear weapons “if necessary.” Russia annexed Crimea in March last year. Putin said in the documentary that the ouster of former Ukrainian President Viktor Yanukovych was an armed coup “masterminded by our American friends.”

On Tuesday, Kremlin spokesman Dmitry Peskov told reporters that Russia would not give back Crimea to Ukraine despite warnings from the European Union and the U.S. that they won’t drop sanctions against Russia. Peskov said Crimea was an integral part of the Russian Federation and “the subject of our regions is not up for discussion.”

Crimea was part of the former Soviet Union until 1954 when the then Soviet leader Nikita Khrushchev gave it to Ukraine. Wladimir Klitschko, an Olympic champion in 1996, said the war in eastern Ukraine made no sense because Ukraine and Russia “are like brothers.” In years to come, Putin will apologize for the aggression and annexation of Crimea, he added.

Europe must show Vladimir Putin where the limits are

When asked what he would say to the Russian President when he came face to face with him, Klitschko responded, “That he is making the same mistakes that have been made in the past.” After witnessing the consequences of the second World War, you just can’t disregard international laws. So far, the fight between Ukrainian government forces and Russia-backed separatists has claimed more than 6,000 lives.

Klitschko urged the Western countries to get more forceful in dealing with Putin. He said the European community was still sleeping, so Putin was doing whatever he wanted to.