UPDATE 1-Russian tycoon cancels asset split on force majeure

(Adds Onexim comment, background)

MOSCOW, Oct 7 (Reuters) - Russian tycoon Mikhail Prokhorov told his former business partner Vladimir Potanin he would pull out of an asset split deal, citing force majeure, a spokesman for Potanin's investment vehicle Interros said on Tuesday.

A spokesman for Prokhorov's investment vehicle ONEXIM appeared surprised by the statement.

"Onexim is unaware of such facts," the spokesman said. "There is no emergency. The group is involved in a range of businesses. Therefore everything related to the asset split appears to be of secondary importance."

The deal involved stakes in metals giant Norilsk Nickel (GMKN.MM) and gold miner Polyus (PLZL.MM).

Last month ONEXIM said that under the deal it would receive some 35 percent of shares in Potanin-controlled Polyus (PLZLq.L), in addition to the around 30 percent it already had. [ID:nLO119055]

In exchange, Potanin would receive a 2 percent stake in Norilsk (NKELyq.L), a 25.8 percent stake in Rusia Petroleum, holder of the Siberian Kovykta gas field licence, and a 95 percent stake in the agribusiness firm Agros.

Prokhorov and Potanin, ranked Russia's fifth- and sixth-richest men respectively by Forbes magazine, shared control of Norilsk, the world's top nickel producer, and Polyus, Russia's biggest gold producer, before announcing their plans to divide assets in January 2007. (Reporting by Polina Devitt; Writing by Aleksandras Budrys; Editing by Greg Mahlich)