US media group Viacom has agreed to buy the UK's Channel 5 for £450m, it has been announced.
Viacom, the owner of MTV, will be acquiring the channel from Richard Desmond's Northern & Shell group.
Viacom described Channel 5 as "one of British television's biggest brands" and said the acquisition would "accelerate" its strategy in the UK.
It added that Channel 5 would complement Viacom's existing pay-TV networks.
As well as MTV, Viacom also owns Comedy Central and children's network Nickelodeon.
Mr Desmond put Channel 5 up for sale in January, four years after having bought it for £103.5m, and was reportedly expecting to raise about £700m.
The sale to Viacom was more in line with analyst forecasts which valued the television station at between £400m and £500m.
The sale reportedly drew interest from more than 20 potential buyers, including Discovery Communications, Scripps Networks and BSkyB, as well as Viacom.
Viacom's president and chief executive, Philippe Dauman, said: "Channel 5's momentum is indisputable, with impactful programming, increasing popularity and a growing digital platform.
"Channel 5's management and employees have done an outstanding job building their brand and we are pleased to welcome them to our team."
Channel 5's chief operating officer, Paul Dunthorne, said the business had been "transformed" since Northern & Shell bought it in 2010.
He added: "The combination of Channel 5 with Viacom's global resources, technology and expertise adds further to the momentum of the business and offers numerous exciting opportunities for the channel's future."
Channel 5 was launched in March 1997 as the UK's fifth terrestrial TV channel.
Its most popular shows currently include Big Brother and Celebrity Big Brother, as well as Australian soap operas Neighbours and Home And Away.