Numericable has formally signed a deal to acquire mobile virtual network operator (MVNO) Virgin Mobile France.

The French cable operator last month announced that it had entered exclusive talks to buy Virgin Mobile in a deal worth €325 million.

On Monday its parent company Altice said Numericable had inked the agreement following discussions with Virgin Mobile's employee representatives. It did not comment on the value of the transaction.

Under the terms of the agreement, Numericable will acquire 100% of the share capital of Omea Telecom (referred to by Altice as Omer Telecom), the holding company that operates under the Virgin Mobile brand in France. Carphone Warehouse owns 46% of Omea Telecom.

"The agreement is dependent upon obtaining approval from the administrative authorities concerned," Altice said in a statement.

Numericable is clearly serious about adding mobile services into its portfolio. The Virgin Mobile deal comes almost three months after it won the race for French mobile operator SFR, beating rival Bouygues Telecom with a €13.5 billion bid.

Virgin Mobile is not having an easy time of it in France. Its 1.7 million customers give it an insignificant share of the market; according to Arcep, there were 77.6 million SIM cards in use in France at the end of March.

When the deal was announced last month, Omea Telecom founder and CEO Geoffroy Roux de Bézieux noted that the company would get a significant boost from aligning itself with Numericable.

"The company will have the means to develop in the high-speed broadband and mobile markets, where marketing and technology investments are becoming increasingly important," he said.