Harsh words have been exchanged and the boys are gearing up for a fight, which began when a few jokey comments turned sour.
War of words: Zayn Malik and Max George
The feud began after 1D's Zayn Malik called The Wanted's Max George a 'geek' and a 'clown' on Twitter last week, after about a year's worth of sly digs at each other - but Max has decided he won't take the insults lying down.
The 'All Time Low' hitmaker called Zayn's bluff and demanded a confrontation in New York, where the band are currently based.
Max told The Mirror: "I don't know what his problem is, to be honest. He seemed to get a little bit serious. I tried to palm it off as friendly but you can only take so many insults.
"Eventually I said: 'If you've got a problem, come and see me in New York and we'll sort it out.'"
Over to you Zayn...