Anatoly Golomolzin told Reuters the amendments had been agreed following a complaint by Rosneft (ROSN.MM) after the Russian state oil company's share swap and Arctic exploration deal with BP (BP.L) collapsed last year in the face of opposition from its Russian partners.

Rosneft appealed to the competition watchdog after the failure of the deal, he said.

"Last year there was a situation linked to the fact that a deal could not take place, BP's deal with Rosneft, and it became clear that it was linked to the shareholder agreement," the deputy head of the Federal Anti-Monopoly Service, told Reuters by telephone.

"Since last year we have been analysing the agreement and have agreed amendments to the law requiring the publication of such agreements."

(Reporting by Vladimir Soldatkin)

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