Zaha opened up on their scrap in England's Under 21 clash against Lithuania eight years ago.
The Three Lions' 5-0 rout was overshadowed by the pair pushing and shoving each other during the match.
Zaha confronted Morrison on the pitch, which resulted in Morrison thrusting his arm into his team-mate's face with Zaha pushing back.
It was left to substitute Nathan Redmond to act as peacemaker, breaking up the clash between the two.
"I just had enough, I was like 'what are you doing? We can all do what you're doing right now, pass the ball' and out of the blue he just pushed me," Zaha continued.
"I'm like 'are you dumb?' so I pushed him back and it was just nonsense on the pitch then when you go inside the man is silent.
"You're trying to push me outside like you're on whatever then when we go inside you're just in your corner on your own so I was like what the hell - it got me really mad because the rest of the team are playing normally but he's doing tricks and then you push me out of the blue.
"Keep that energy when we go indoors but he didn't. It's not like I'm trying to beef people but it's like "what are you on? Why are coming on like you're better than everyone else?" So that annoyed me."
Morrison responded to Zaha's claims by writing several posts on Instagram. On his story he wrote: "Wilfried lol," while he also commented: "Come on, let's jump on a three-way live and state facts, what a dude."
He also posted on the social media platform: "Silent... please come on, let's talk serious, haha baffled."
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