The Daily Telegraph and The Sunday Telegraph have been put up for sale.
The move is part of a review of Sir Frederick and Sir David Barclay's assets in Britain and was first reported in The Times.
Rumours that the newspapers were to be sold have circulated for some time. The Barclay family has owned The Daily Telegraph and The Sunday Telegraph since 2004.
Earlier this month, Telegraph Media Group reported operating profit of £8.1m in 2018, compared with £21m in 2017. The company said the decline was "entirely expected".
The Barclay brothers also own The Ritz, which is already up for sale. Other assets include The Spectator, delivery company Yodel and retailer Shop Direct.
Telegraph Media Group declined to comment.