French telecoms entrepreneur Xavier Niel and his firm Iliad have reached a deal to take over Ireland's leading operator eir, adding to his firm's expansion plans into Italy.

Niel's personal holding company NJJ and Iliad will each take 31.6 percent stakes in eir, which boasts the nation's largest fiber optic network, for a total of 640 million euros ($758 million), Iliad said in a statement.

Niel shook up France's telecommunications market with his operator Free, which first offered cut-rate and hassle-free home internet, phone and TV service and then moved into mobile services.

Iliad is the parent company of Free.

Eir, the former historical monopoly operator in Ireland, has a leading position in fixed broadband and is a challenger in the mobile segment.

It earned 520 million euros in operating profit in its 2016-2017 financial year on sales of 1.3 billion.

The deal must still be approved by regulators.

With its entry into Ireland, Iliad is expanding into its third European market as it is expected to begin offering services in Italy at the beginning of 2018.

Its arrival in Italy with a low-cost offer could prove as disruptive as in France, where its launch of mobile services in 2012 led to a fierce price war between operators.