AT&T Inc. is in talks to combine its sprawling WarnerMedia division with Discovery Inc., potentially unwinding the telecom behemoth’s signature bet on media, as pressure on the traditional entertainment business mounts.The talks, which likely value the AT&T business at well over $50 billion with debt, could lead to an agreement by Monday, who cautioned that the talks could still fall to pieces.A deal between WarnerMedia and Discovery would further integrate a media business pounded by cord-cutting and competition from video streaming. WarnerMedia owns cable channels such as HBO, CNN, TNT and TBS as well as Warner Bros. television and film studio. Discovery has a portfolio that includes its namesake network and HGTV.Discovery Chief Executive David Zaslav is expected to head the new company. It is not clear whether Jason Kilar, the current chief executive of WarnerMedia, will remain on the lesser role.