Repsol is taking further legal steps against Argentina for seizing the Spanish oil company’s controlling stake in YPF – Argentina’s biggest energy firm.
Repsol has filed a complaint with the World Bank’s international arbitration forum calling the nationalisation “unlawful and discriminatory”.
Legal specialists say it could take more than a year to complete the arbitration process.
Repsol has also sued Argentina through a US court and has threatened legal action against companies that invest in YPF.
Argentine President Cristina Fernandez nationalised YPF in May, accusing Repsol of not investing enough to boost output at a time of growing demand.
Repsol has denied under-investing in YPF.
Fernandez’s takeover of YPF drew strong criticism from the European Union and several other key trade partners already unhappy with Argentina’s import curbs and other unorthodox policies aimed at boosting its trade surplus.