Adds details on appointment, executive comment, context, background

July 24 (Reuters) - BT Group BT.L, Britain's largest broadband and mobile provider, named Patricia Cobian, currently with rival Virgin Media O2, as its first female chief financial officer on Thursday, succeeding long-time finance chief Simon Lowth.

The change comes more than a year after CEO Allison Kirkby took the helm at BT amid a transformative plan set in motion by her predecessor Philip Jansen.

Lowth, who became CFO in July 2016, played a key role in implementing the company's cost-cutting measures and sharpening its strategic focus.

BT has been investing heavily in its British fibre network, which now covers more than 19 million premises. It also plans to cut more than 40,000 jobs and about 3 billion pounds ($4.07 billion) in costs by 2030, and possibly shed its foreign business to sharpen domestic focus.

"(Cobian's) leadership, deep industry experience and knowledge will be invaluable, as we continue our once-in-a-generation upgrade of the UK's digital infrastructure and accelerate BT's modernisation," CEO Kirkby said in a statement.

BT separately reported a 1% decline in first-quarter core profit, weighed down by falling legacy voice services and handset sales, which offset cost cuts and demand for its fibre broadband services. However, the company said it was on track to meet its full-year outlook.

After serving as finance chief for Telefonica's UK mobile network O2 since 2016, Cobian moved into the same position at Virgin Media O2 in 2021, following the 50-50 joint venture between Telefonica TEF.MC and Liberty Global LBTYA.O.

Cobian will join BT next summer, coinciding with Lowth's retirement.

The appointment was first reported by The Telegraph on Wednesday.

($1 = 0.7371 pounds)

(Reporting by Pushkala Aripaka and Nithyashree R B in Bengaluru; Editing by Sherry Jacob-Phillips)

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