It is a dated but ordinary piece of office equipment of the kind that might normally only attract the attention of retro-conscious hipsters.

But the rotary dial Bakelite telephone that went under the hammer at a Maryland auction house this weekend is not just a curiosity from the pre-digital age.

It is Adolf Hitler’s personal travelling telephone, which the dictator almost certainly used to issue orders that led to the deaths of millions.

The Seimens W38 phone sold for $243,000 (£195,000) on Sunday. Andreas Kornfeld of Alexander Historical Auctions said the bid was made by phone, the auction house does not disclose the names of buyers.