If they were children they’d probably be told to grow up, but no one tells billionaires what to do.

That’s why two of the world’s wealthiest men are refusing to back down in their ongoing ‘mine’s bigger than yours’ battle to be the owner of the world’s largest yacht.

Megarich Russian tycoon Roman Abramovich, who currently owns the world’s biggest private superyacht, appears to have been forced to extend his vessel’s length after United Arab Emirates Sheikh Mohammed bin Rashid launched a bid to regain the title.

It was only two years ago that Abramovich bought his 557-foot vessel and stole the crown from the Sheikh’s 532-foot yacht called Dubai.

In the wake of rumors that the Sheikh is having his boat extended to recapture the title, Ambramovich has booked his own yacht for a refit.

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