Adds detail from statement

LONDON, July 23 (Reuters) - BT BT.L, Britain's biggest telecoms group, said it would meet its target of reaching 25 million British homes with its full fibre network by the end of December, as it reported flat quarterly revenue and reiterated its annual guidance.

CEO Allison Kirkby called it a "solid start" to the year, a quarter during which she announced a joint venture with Verizon VZ.N to combine the pair's international enterprise operations, allowing BT to fully focus on its home UK market.

"We achieved record new full fibre connections and take-up, resulting in fibre contributing to more than half of our broadband revenues for the first time," Kirkby said in a statement on Thursday.

For the three months to the end of June, BT posted flat revenue of £4.3 billion ($5.76 billion), and adjusted earnings of £2 billion, down 1% year-on-year, and said it was on track to meet guidance for free cash flow to rise to £2 billion this year, from £1.5 billion.

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