Algeria has provisionally appointed law firm Shearman & Sterling LLP to advise it on the nationalisation of Orascom Telecom's local mobile phone unit, the official news agency reported on Monday.

The firm is scheduled to complete within 100 days a valuation of the Djezzy unit, the subject of a long-running dispute between the Algerian government and Orascom Telecom, the official APS news agency reported.   

Djezzy has been Orascom Telecom's biggest single source of revenue and uncertainty over its future has confused a planned $6.6 billion deal for Russia's Vimpelcom to acquire Orascom Telecom assets.

Algeria's government has hit Djezzy with hundreds of millions of dollars in back taxes and barred it from moving profits abroad. It also blocked Orascom Telecom from selling the unit to South Africa's MTN.

Orascom Telecom reluctantly agreed to enter talks on nationalisation, but there is still no clarity about whether the state will buy all or part of Djezzy, how much it will pay and how long the process might take. - Reuters