LONDON, Feb 27 (Reuters) – A lawyer for a Cyprus-based company, Crispian, owned by Russian businessman Roman Abramovich and his partners, has asked a London court on Tuesday for permission to proceed with a sale of 2 percent in mining giant Norilsk Nickel to billionaire Vladimir Potanin. Potanin’s Cyprus-based company, Whiteleave, exercised its right to buy 2 percent in Nornickel last week, giving Crispian five days to hand over the shares, the lawyer told the London court. That five days expires on Feb. 28, he added.