Former boxing champion and leading politician Vitaly Klitschko has pulled out of Ukraine’s presidential elections planned in May.

Vitaly Klitschko said instead he would back tycoon Petro Poroshenko.

Both men played a key role in months of street protests that led to the ousting of President Viktor Yanukovych.

Vitaly Klitschko, 42, announced his decision to pull out of the presidential race at his Udar (Punch) party’s gathering in Kiev on Saturday.

“The only chance of winning is to nominate one candidate from the democratic forces,” he said.

He stressed that a contender with “the highest chances to win should be running” for the presidency.

“Today, Petro Poroshenko is this candidate,” Vitaly Klitschko said, reminding supporters that the two politicians had stood and fought shoulder-to-shoulder at the protesters’ main camp in Kiev – the Maidan.

Petro Poroshenko, 48, has already declared his intention to enter the race.

Vitaly Klitschko has pulled out of Ukraine’s presidential race and he will back tycoon Petro Poroshenko (photo AFP)

The owner of the popular Roshen chocolate company, Petro Poroshenko is widely known in Ukraine as the “chocolate king”.

He has held a number of cabinet portfolios under different presidents in the past decade.

On Saturday, Petro Poroshenko said that – together with the Udar party – “we declare our goal is a new Ukraine”.

“Our goal is to live in a new way. To form Ukraine in a way that there will be rich, free and honest citizens happy to be Ukrainians and to live in a country respected by the whole world.”

Vitaly Klitschko’s withdrawal means the race is likely to be between Petro Poroshenko and former PM Yulia Tymoshenko.

Several former supporters of Viktor Yanokovych have also announced they will run. The Party of Regions, to which Viktor Yanukovych belonged, on Saturday backed former Kharkiv governor Mykhailo Dobkin to run for the presidency.

The May 25 elections are seen as a crucial step in leading Ukraine out of the country’s deepest political crisis since its independence in 1991. An interim administration is currently in place in Kiev, led by acting President Olksandr Turchynov and PM Arseniy Yatsenyuk.

Russia says the current authorities in Kiev came to power in a coup and are, therefore, illegitimate.

Ukraine – backed by the West – denies the claim.

Moscow formally annexed Crimea after the predominantly ethnic Russian region held a referendum earlier this month which backed joining Russia.

Latest opinions polls give Petro Poroshenko about 25% of the vote, ahead of his presidential rivals, while Vitaly Klitschko and Yulia Tymoshenko are lagging far behind.

However, Yulia Tymoshenko, 53, who was released from prison last month following the overthrow of Viktor Yanukovych, is expected to mount a strong campaign.

In all, 15 contenders are planning to challenge for Ukraine’s presidency.

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