Nickelodeon star Ariana Grande and Australian star Jai Brooks have rekindled their romance and were spotted sharing a kiss backstage at the 2014 iHeartRadio Music Awards.

The couple broke up last year in October, when Brooks accused Grande of cheating on him with The Wanted's Nathan Sykes whom she dated back then.

"Yes I was cheated on. Yes it does s**k. Yes I was left for another man," the 19-year-old tweeted.

"Nathan if you read this, when you hold her hand you better hold it tight because you are holding my world," he added. "I do wish you two happiness and a good life and hope everything works out."

The Victorious actress responded in a series of tweets, writing, "You said to me if I didn't come back to you, you'd make me look bad to the entire world... I'm no longer afraid of you or your lies anymore."

"I'm going to be the lady my mother raised and carry myself with class and dignity... But I will never be any man's press opportunity," she continued, later adding, "I'm finally happy. Words can't hurt me anymore."

However, Brooks apologised for his Twitter rant and the two have moved on from the fight.

"They are together and very happy," a source told Hollywood Life. "They have been seeing each other daily for a while now. He apologized for making up all the lies about her cheating and they are back!"