Henderson was not part of manager Gareth Southgate's initial squad after missing Liverpool's last three Premier League games due to a hamstring injury but the club said he was recovering well.
"Henderson has made good progress in his recovery from a hamstring problem and is set to return to full training this week," Liverpool said in a statement.
The midfielder, who has won 69 caps, has made one international appearance this year in a 2-1 friendly win over Switzerland in March.
His return to the England squad comes after Manchester City midfielder Kalvin Phillips withdrew due to a shoulder problem.
England, who have two defeats and two draws from their four Nations League group matches so far, play Italy in Milan on Friday and host Germany at Wembley three days later.
Henderson will compete with Declan Rice, James Ward-Prowse and Jude Bellingham for a spot in the heart of midfield.
