The pair are firm friends now, even sharing a mini reunion over the weekend in Madrid.
But back when they formed 1D with Harry Styles, Niall Horan and Zayn Malik, the lads clashed over their mutual desire to be leader.
Speaking on Hits Radio, Liam, 26, said: When we were in the band it kind of felt like, because he was the oldest and because Id been singing for quite a bit of time we both got put in a weird position. He was wanting to be the leader, and I was doing my thing and wanted to.
So, at first we didnt get on at all. We absolutely hated each other, it was so funny. Really bad. We hid it well.
Thankfully, the lads became friends – although the same cant be said for Louis and Zayn, as Louis, 27, revealed their friendship never really got better after Zayn failed to support his former bandmate as he performed on The X Factor days after his mum died.
Since the bands hiatus (were still not OK) in 2016, each of the lads has carved out their own sound in their solo careers.
Liam, who is promoting his new single Stack It Up, said: We do such different stuff. Me and Harry are chalk and cheese, we are the other ends of the One Direction spectrum in terms of what we actually do. I wouldnt do some of the stuff he does, same as he wouldnt do some of the stuff I do.
More: One Direction
I feel like Niall was the biggest One Direction fan out of all of us. He still has most of the same team that we all had before.
I feel like Slow Hands could almost have been a bit of a One Direction song. Everyone is doing their own thing which I think is the best thing ever.
But dont let that get in the way of a reunion, guys. Guys?!
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