Virgin Media, which supplies TV and broadband services to just under 5m UK customers, is being bought by US-based company Liberty Global in a deal worth $23.2bn (£15bn).
Colorado-based Liberty Global already operates services in a range of countries around the world, including in Belgium, Germany and the Netherlands, and has a growing presence in South America, with 1m subscribers in Chile.
Adding Virgin Media to the portfolio will mean it's serving 25m customers in a total of 14 countries, with 80% of its revenues coming from European customers.
The stock and cash deal will see the Virgin Media name continuing to operate in the UK, but it's expected some cost-savings will be made by centralising some parts of the company's operations, and consolidating duplicated functions.
Virgin Media announced a 30% increase in operating profit last year, at just under £700m: the company was created in 2008 with the merger of NTL, Telewest and Virgin Mobile, with Virgin founder Sir Richard Branson retaining a 3% stake in the company in return for a 30-year brand licensing agreement.
Financial commentators are speculating that the deal will see battle rejoined between Liberty Global's chairman, billionaire John Malone, and BSkyB's Rupert Murdoch.
The two have previous form, having been rivals for control of the largest satellite TV company in the States, DirecTV, a few years back.
BSkyB currently dominates the UK market for pay-TV, with 10.7m customers; Virgin has 4.9m UK subscribers.