Newport took a deserved lead through Shane McLoughlin’s 11th-minute penalty before Hakeeb Adelakun levelled from the spot after the half-hour mark.
Rumarn Burrell bagged the opener in the 10th minute, with former Royals striker Jon Dadi Bodvarsson making it two. It looked like goals from Michael Craig and Sam Smith would earn Reading a point ...
Peterborough’s goal came in the 19th minute when Tayo Edun’s cross was met by a diving header from Mahamadou Susoho that went in off the post.
The game at the Valley was settled with two first-half goals, putting the south London club one point off the play-offs.