Xavier Niel has launched a tender offer to take the French telecoms company he founded 22 years ago private.

The billionaire already owns around 71 percent of Iliad. Remaining shares in the company jumped 61 percent following Niel's offer.

The company operates its consumer telecoms business under the brand name Free. It also wholly owns data center company Scaleway.

The 'European Cloud Company' operates across four main data centers in France and another in The Netherlands. Its biggest, DC5, spans 15,000 sq m (161,500 sq ft) of high-density space and supports more than 28MW of IT power.

Niel believes the company is undervalued in the public market, after shares in the company have suffered over the past few years.

Investors are concerned about Iliad's heavy spending on 5G and fiber, a price war in France, and an expensive expansion into Italy. While that latter venture is now turning profitable, Iliad is now planning a similar push into Poland, with a $1.9 billion offer for Liberty Global's operations in the country.

“From now on, a new phase of development for Iliad will require quicker transformations and significant investments that will be easier to carry out as a private company,” Niel said in a statement. “Our ambition for Iliad is to accelerate to become a leader in telecommunications in Europe.”