British telecommunications company BT Group has sold its iconic BT Tower for £275 million (US$347 million, €321.3 million) to hotel management company MCR Hotels.

The 620ft telecommunications building opened in 1964 and was once the tallest structure in London until 1980 when it was surpassed by the NatWest Tower.

MCR – claimed to be the US’ third-largest hotel owner-operator – plans to transform the Grade II listed London landmark into a hotel.

Brent Mathews, property director of BT Group, said: “The BT Tower sits at the heart of London and we’ve been immensely proud to be the owners of this important landmark since 1984.

“It’s played a vital role in carrying the nation’s calls, messages and TV signals, but increasingly we’re delivering content and communication via other means. This deal with MCR will enable BT Tower to take on a new purpose, preserving this iconic building for decades to come.”

Payment for the sale will be made over multiple years, as BT equipment is progressively removed from the 37-floor building, with final payment on completion of the purchase.

The company will take several years to vacate the premises, due to the scale and complexity of the work to move technical equipment.

MCR will partner with London-based architecture and design firm Heatherwick Studio to consider how best to reimagine the building’s use as a hotel.

The company owns 150 US hotels including the TWA Hotel, The High Line Hotel and Gramercy Park Tavern in New York City.

Tyler Morse, CEO and owner of MCR, said: “We’re proud to preserve this beloved building and will work to develop proposals to tell its story as an iconic hotel, opening its doors for generations to enjoy.”