Jennifer Lawrence and Chris Martin were all over each other at the iHeartRadio Music Festival.

The couple, who started dating in late June following the Coldplay frontman's split from Gwyneth Paltrow in March after 10 years of marriage, reportedly couldn't keep their hands off each other backstage at the event over the weekend.

A source told gossip website RadarOnline.com: ''At around 7pm on Friday night, Jennifer and Chris were making out backstage in an area that only allows security and a select group of celebrities in.''

The insider added: ''She had her arms around his neck. They were kissing passionately before he took the stage!''

The 'Hunger Games' beauty cheered on the British rocker, 37, when he eventually took to the stage at the MGM Grand Arena in Las Vegas with his bandmates.

The eyewitness said: ''Jennifer was watching from backstage and looked like the proudest girlfriend in the world!''

After three months of dating, the duo finally appear to be ready to go public with their romance.

The insider added: ''They spent the entire weekend together. They were not trying to hide it at all.''

The 24-year-old actress split from her long-term boyfriend Nicholas Hoult earlier this year.