Naughty Boy, real name is Shahid Khan, was working with Zayn on his solo career until the pair fell out last year (15) when the producer was accused of leaking his former friend's music online.

He has once again started up their war of words, by calling Zayn out for taking credit of writing his debut solo single Pillowtalk when the song actually has four other writers - Anthony and Michael Hannides, Levi Lennox, collectively known as MakeYouKnowLove, and Joe Garrett.

When a fan asked Zayn on Twitter which song he wrote first, Zayn simply replied, "Pillowtalk". Naughty Boy retweeted the comment and added, "LOL (laugh out loud)" before following it up with the tweet, "Credit where credit is due."

After receiving backlash on social media, Naughty Boy then threatened to release the original version of Zayn's second single Like I Would. In a now-deleted tweet, he writes, "Don't make me leak the original #likeiwould ha."

He later explained his earlier posts, telling followers, "This ain't about me.. its just about giving credit to @MakeYouKnowLove for writing an amazing song, thats (sic) all.. bless. have a great day."

Zayn has not responded to the criticism.

In December (15), the producer told Britain's Daily Mirror newspaper he was hoping to be friends with Zayn in the future.

"I think I'd reach out to him," he said. "But if anything is meant to happen, and fate wants it to happen, it will... I think at the moment he's doing what he needs to do and I'm doing what I need to do... There's no bad blood - I don't feel angry towards him. Life is too short."