Piers Morgan has signed a £5.5m (€6.6m) deal to replace Larry King.
The 'Britain's Got Talent' judge agreed to the four-year contract with US network CNN and will work for 30 weeks of the year so is expected to move to the States.
A source told The Sun newspaper: "Bosses were impressed by the quality of Piers' interviews."
Chat show legend Larry is due to step down from 'Larry King Live' later this year and rumours had been rife as to who would replace the 76-year-old interviewer.
American presenters Ryan Seacrest and Katie Couric were said to be in the running but producers thought former newspaper editor Piers would make the ideal replacement.
However, Piers' new deal means he will have to quit his role on the 'Britain's Got Talent' judging panel because he won't have enough time to commit to the programme - although he has vowed to stay with 'America's Got Talent'.
A source previously said: "No matter how much Piers wants to stay on 'BGT', he just can't do it all, simple as that.
"The new series of 'America's Got Talent' opened to record ratings last week so NBC are insisting he stays with that show."