Telefonica said that Sony Mobile will be among its partners for its rollout of devices powered by Firefox OS, which is scheduled to begin later this year – although the first tranche of smartphones are set to come from Alcatel and ZTE.

In its Q1 2013 earnings release today, the Latin American and Europe operator group said: “The first [Firefox OS] devices from Alcatel and ZTE followed by LG, Huawei and Sony, will be launched in Spain, Colombia and Venezuela in the third quarter of 2013 and, along the fourth quarter of 2013, in five more countries, including Brazil.”

Telefonica and Sony announced a partnership earlier this year which included “laying out a joint technical collaboration to explore the development of a handset running Mozilla’s Firefox OS open source mobile platform”.

At the time, Bob Ishida, head of the products business group at Sony, noted: “Our engineers are now working with Firefox OS Mobile and HTML5, evolving technologies which show great potential. In addition, we continue to work with our operator partners, including Telefonica, on a development project with an ambition to bring a product to market in 2014.”

The company has already released an experimental Firefox OS build for its Xperia E device for developers, “to get valuable feedback”.

Sony Mobile today reiterated that this is its position.

At Mobile World Congress this year, Mozilla said that Huawei and LG had joined its vendor partners, alongside Alcatel One Touch and ZTE. ZTE has showcased devices running on the platform.