The decision by the European Commission (EC) to open a formal investigation into whether a €9bn ($9.8bn) loan made to France Télécom by the French government constitutes unlawful state aid could scupper the French telecoms company's planned €15bn rights offering.

The EC said this week that it is investigating the legality of the credit facility granted to the indebted French company by ERAP, a special purpose vehicle for the French government. The investigation is expected to last between 12 and 18 months.