Miner and metals producer Alumina has fended off allegations it is trying to obstruct the global demerger of US aluminium giant Alcoa and says it will defend its rights in US court proceedings.
Alumina's statement comes after its larger partner in the Alcoa World Alumina and Chemicals (AWAC) joint venture filed a complaint in a Delaware state court in the US on Friday.
Alcoa has claimed its Australian partner has threatened "to create a cloud over the demerger" unless Alcoa grants it highly valuable concessions with respect to AWAC's ownership and operation.
The company has asked the court to declare Alumina's rights with regard to the demerger.
The US-based metals giant announced in September 2015 it would break its global operations into two independent, publicly-traded companies - one focused on upstream mining and smelting and the other on aluminium products, in an effort to tackle the commodities slump.
The AWAC JV, formed in 1994, is to remain part of the upstream unit. It includes bauxite mines, three alumina refineries in Western Australia and an aluminium smelter, which together employ around 5,000 people.
Alumina said under the demerger, Alcoa is seeking to exit AWAC and introduce a new and financially weaker entity into the partnership.
It also believes the breakup will trigger first offer rights in its favour, as well as entitle it to receive various offers, including for Alcoa's 60 per cent stake in AWAC.
"Alumina has serious concerns that the proposal as described by Alcoa will result in a material adverse change in the nature, size, scope and financial wherewithal of our partner in AWAC," it said in a statement.
Both companies are expected to separately continue discussions over the JV arrangement.
At 1337 AEST, Alumina shares were up 0.25 cents at $1.4375 each.
