When Roku said it would start shipping its media streaming boxes to the U.K. for the first time last month, there was a significant omission from the lineup of services it was offering — the BBC’s iPlayer.

The iPlayer is the dominant force in Britain’s streaming TV landscape, available everywhere from the PC to cable to mobile, and responsible for nearly two billion viewings in 2011 alone.

No surprise, then, that today Roku is announcing that it’s launching an iPlayer channel for its British customers, allowing them to access the service’s library of popular television programs through their devices.

The moves adds a real backbone to the service — which already boasts a lineup including UFC, Fox News, and Netflix, which launched last month in the U.K and Ireland.

“This is among the first of many significant content partnerships for Roku in Europe and we look forward to making additional announcements in the coming weeks,” said the company’s European boss, Clive Hudson.

Rumors continue to circulate that will soon add Netflix competitor Lovefilm, but the deal with the BBC makes a big difference for anyone purchasing a Roku box, which are priced locally at £49.99 and £99.99 ($79 and $158).

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