Producer Naughty Boy has hit back at One Direction star Louis Tomlinson over a song featuring the boyband's former member Zayn Malik.
Tomlinson criticised Naughty Boy - real name Shahid Khan - after the producer put a track f eaturing Malik singing over an acoustic guitar online, in the wake of his departure from One Direction.
"Wow @NaughtyBoyMusic you're so inconsiderate pal, seriously how f****** old are you ? Grow up ! #masterofallwisdom,'' Malik's former bandmate Tomlinson wrote on Twitter.
It was initially thought that Malik had put his vocals to a solo track but it later emerged that it was recorded for the boyband's last album.
Now Naughty Boy has told Heat magazine that Tomlinson was stirring up trouble with his Twitter outburst.
"There seems to be some needless provoking going on. [Louis] was deliberately adding to the provoking.
"I don't think that's fair. Especially on Zayn, that's not fair. Right now, there needs to be calm."
He added of Tomlinson: "He could have said that to me privately. Doing it openly is another act of provocation that's not needed."
Naughty Boy told the magazine that Malik had been under intense pressure and was in a studio with him because he wanted to enjoy time with his friend.
Malik had raised eyebrows when he was spotted at the studio with Naughty Boy, despite saying that he wanted to spend time as a "normal 22-year-old" away from the spotlight.
"I've been his friend. He needs one," Naughty Boy told Heat.
"Just because we were seen at my studio - you [don't] necessarily just make music. People seem to forget that he's under so much stress. Which is why he left the tour.
"There's a lot going on. People get caught up - what he has done is to be normal. Sometimes being normal is to try and sort things out with your fiancee or hang around with a friend. That is normal."
Naughty Boy, who has also worked with Sam Smith and Ed Sheeran, also added: "If people knew the truth."
Malik quit One Direction after jetting back to Britain having been ''signed off with stress'' amid reports he had cheated on his 21-year-old fiancee, Perrie Edwards.
He insisted there is no bad blood between him and his former bandmates, who have been ''really supportive''.
Malik and Edwards recently put speculation about the future of their engagement behind them, as they were pictured enjoying a romantic break.