Spain Stings Argentina Over Nationalization of Repsol YPF MADRID - Spain said Friday that it would seek to restrict imports of biodiesel fuel from Argentina, its first retaliatory measure after the government in Buenos Aires decided to seize control of the assets there of Repsol YPF, the largest Spanish oil company. Soraya Sáenz de Santamaría, the deputy prime minister, said Spain would seek to use Spanish and European biofuel instead of that of Argentina, which is the biggest exporter of biofuel to Spain. Madrid imports almost three-quarters of all its biofuel, with shipments from Argentina worth about €750 million, or $991 million, last year. Still, the measure fell short of the kind of hard-hitting sanctions that had been threatened by Spain. Several government ministers warned in recent days that Argentina's decision was an act of aggression against Spain and would not go unpunished. Following a cabinet meeting in Madrid, Ms. Sáenz de Santamaría would not comment on what further actions might be taken by Madrid, nor even detail how the biofuel restrictions would be applied. The diplomatic tussle follows last Monday's announcement by President Cristina Fernández de Kirchner that Argentina would take back majority control of YPF, now 57 percent owned by Repsol. Even before the response from Madrid on Friday, her government played down the impact that such sanctions could have on Argentina. Repsol is planning to challenge the Argentine government before the international courts and seek at least $10.5 billion in compensation for the expropriation in what promises to be a lengthy legal battle. Matthew Parish, a Geneva-based international arbitration partner at the law firm Holman Fenwick Willan, noted that Argentina was already the world's biggest defaulter on investment arbitration awards. The Spanish government has been studying what sanctions it could impose under the terms of a bilateral investment treaty signed with Argentina in 1991. However, trade lawyers have warned that Spain needed to consider the risks that any escalation in the conflict would present to the significant assets of other Spanish corporations operating in Argentina - a further reason to opt instead for sanctions at the European Union level. The Union is Argentina's second-biggest export market after Brazil. The Union could, for instance, freeze ongoing talks about forming a free trade area with Argentina or suspend some trade concessions granted to the country. On Friday, lawmakers from the European Parliament approved a resolution urging the European Commission to remove such concessions on Argentine exports.