Rio Tinto is set to start face-to-face negotiations with the government of Mongolia as its seeks to complete the USD 6.75bn expansion of a huge copper project in the Gobi desert.

The Anglo-Australian group is sending a team of senior executives to the capital Ulaanbaatar to try and hammer out a new financing agreement so that the development timeline can be maintained and underground caving operations can start later this year.

The discussions will focus on a number of issues including tax, a new power agreement and benefit sharing, according to people with knowledge of the situation.

Some government officials want Rio to pay more than USD 300m of withholding taxes on income it has received from Oyu Tolgoi LLC, the Mongolian holding company that owns the mine.

Rio receives a management service fee for running Oyu Tolgoi’s existing open pit and the underground project as well as interest on money it has lent the government to fund its share of the development costs.

However, the officials say it is “very difficult, if not impossible” to engage constructively on the issue because the payments are the subject of arbitration in London.

For its part, Rio believes the issue of withholding taxes is dealt with in the separate investment and shareholder agreements that cover its operations in the country.

The underground expansion of Oyu Tolgoi ranks as Rio’s most important growth project. At peak production it will be one of the world’s biggest copper mines, producing almost 500,000 tonnes a year.

Although Rio runs the existing operations and is in charge of the underground expansion project it does not have a direct stake in the mine.

It’s exposure comes through a 51 per cent stake in Turquoise Hill Resources, (TRQ) a Toronto-listed company. TRQ, in turn, owns 66 per cent of Oyu Tolgoi LLC, with the rest controlled by the government of Mongolia.

The project has been beset by difficulties and is already two years late and USD 1.5bn over budget. The government said earlier this year that if the expansion is not economically beneficial to the country it would be necessary to “review and evaluate” whether it can proceed. ( source: Financial Times)