The ‘Strip That Down’ singer has spoken out against Zayn, who quit the band in March 2015 to pursue a solo career.
Since leaving the other boys behind, Zayn has gone on to make numerous negative comments about his time in 1D - something which has clearly annoyed Liam.
During an interview with The Sun, Liam said he can not understand why Zayn feels that way, explaining: “He doesn’t really support the cause.
Zayn has remained distant from the rest of 1D since his departure, even having a public spat with Louis Tomlinson, after he made a series of digs on Twitter.
Zayn tweeted: “Remember when you had a life and stopped making bitchy comments about mine?”
However, they later seemed to put their differences aside when Zayn publicly reached out to Louis following the death of his mother last December.
Meanwhile, Liam has been busy making a series of revelations about his relationship with Cheryl, hinting they had married during an interview earlier this week.