** Hong Kong-listed shares of Russian aluminium producer OK...

** Hong Kong-listed shares of Russian aluminium producer OK Rusal 0486.HK jump 12.1% to HK$3.88, their biggest daily pct gain since March 24

** Stock hit the highest since April 26, on track for the second session of gains; biggest pct gainer in the Hang Seng material index .HSCIM

** Rusal RUAL.MM has filed a lawsuit against global miner Rio Tinto (RIO) , seeking to win back access to its 20% share of the alumina produced at a jointly owned refiner in Queensland

** The lawsuit challenges Australia's response to Russia's invasion of Ukraine, which included wide-ranging sanctions against Russian firms and oligarchs who had links with President Vladimir Putin

** Rio stepped in to take sole control of Queensland Alumina Ltd in April, sidelining Rusal and cutting its access to the refinery's output of alumina, a compound from which aluminium is derived. Rio owns 80% of the refinery, while Rusal owns the remaining 20%

** Rio (RIO) shares slip 0.4% ** Hang Seng's material index .HSCIM jump 3.4%, while the Hang Seng Index .HSI rises 1%

** As of last close, Rusal's Hong Kong stock had dropped 54.2% this year