The European Union has filed a suit at the World Trade Organisation against Argentina's import restrictions.
The BBC reports it is the latest step in the row between the two since Argentina nationalised energy company YPF, which was majority owned by Spain's Repsol.
EU officials highlighted difficulties with getting export licences as well as rules forcing some companies to import as much as they export.
Trade commissioner Karel De Gucht said the restrictions violate international trade rules.
The case is not directly linked to the nationalisation of Repsol, but Mr De Gucht said the trade and investment climate in Argentina is clearly getting worse.
Last week, Repsol and the investment firm Texas Yale Capital Corp sued Argentina, demanding that it makes an offer for the YPF stake.
The EU is asking for direct talks with Argentina in the first instance. If there is no agreement within 60 days, the WTO will be asked to rule on the issues.
European Union exports to Argentina are worth €8.3 billion a year. European countries import €10.7 billion of goods and services annually from Argentina.
