Bouygues Telecom, the French number-three operator, made its 4G service available to customers without a price hike, following the lead of new entrant Free Mobile last week.

Bouygues said it is “including 4G in its full range of plans currently available, at no extra cost,” with customers already on these plans being upgraded to 4G for free, and without having to sign up to a new minimum term contract, if they have a compatible phone.

The operator said the move will encourage “the development of usage” of its 4G network, which it claims is the biggest in France, covering 63 per cent of the population.

The company did not specify if pricing would change for customers already subscribing to its 4G services.

French new entrant Free last week announced the launch of its 4G services “at no extra cost and still on a no-commitment basis”. By offering 4G with its €19.99 monthly plan, Free said it is “offering a price that is five times cheaper than that proposed in the market for this type of 4G plan”.

The move ramped up the pressure on France’s incumbent operators Bouygues, Orange and SFR, who hoped to charge higher prices for 4G services to recoup some of the profits hit by the arrival of Free.

Free’s 4G launch was criticised by French politicians who expressed concerned that the low price could harm investment and employment in the telecom sector.

Arnaud Montebourg, industry minister, and Fleur Pellerin, junior minister for telecom and digital issues, warned that “a new price war would weaken the ability of operators to maintain significant levels of investment in telecommunications infrastructure”.

French market leader Orange was reported by Reuters to be sticking with its plan to increase its 4G prices in February next year, arguing that “coverage and quality are fundamental”.

SFR was the first French operator to launch 4G in November 2012, with Orange following a month later. Bouygues launched its 4G network at the beginning of October 2013, offering a free one-month trial to the 40 million people in its LTE coverage area until 17 November.