SSE PLC (LSE:SSE) reportedly rejected a takeover approach by Portuguese power firm EDP earlier this year.
According to Reuters, EDP approached FTSE 100-listed SSE in May, with talks taking place between the companies’ leaders before ending in June.
EDP chief executive Miguel Stilwell d'Andrade was said to have initiated these as part of a bid to create a more regionally diverse utility.
SSE chief executive Alistair Phillips-Davies and chair John Manzoni both also reportedly took part, before SSE ultimately rejected the advance in favour of continuing independently.
A deal would have created one of Europe’s largest utilities, boasting a market capitalisation of more than US$44 billion (£33.6 billion).
SSE, which is the larger of the two with a market cap of £21 billion as of Tuesday, is among the UK’s biggest power generators, operating the likes of offshore wind farms and also thermal and gas storage.
Combined, its renewables produced 5.3 terawatt-hours worth of power over the past six months, according to an update said earlier in October.
This left the company on course for interim earnings per share of 45p, SSE added at the time, against 37p over the first half of last year, when operating profit sat at £693.2 million.
Whether EDP will revisit its approach remains unclear, with the talks following a 43.5% surge in power sector dealmaking to nearly US$110 billion this year.
SSE shares climbed 2.2% to 1,915p on the news.