It was announced this week that Salah will leave the Reds this summer after nine years at Anfield.
Currently with the Scotland squad, Liverpool fullback Robertson said: "Mo and I have been close since day one, we signed in the same window in the same summer."He helped me right from when I first came in.
"I signed from Hull and maybe didn’t have as much belief in myself as I should have. I saw myself in the early days as a Hull player playing against these lads instead of being a Liverpool player.
"There were a few people who had a big impact on me in that early stage — James Milner, Jordan Henderson, Adam Lallana — good people around me.
"They gave me the belief in what I could go on to achieve and Mo was a big part of that.
"With Mo, every minute of every day is dedicated to football and that’s why he’s in peak condition. I’m not sure I’ve got a six-pack like him, although I’ve tried!
"He is in unbelievable condition, very rarely injured and looks after himself. That mentality, that’s what you need to be at elite level.
"We grew together. He became one of the best players in the world and it was great to sit back and watch him.
"His goals bailed us out of a hole so many times, he’s been fantastic for the club and I don’t think anyone will argue with that.
"Our families sit next to each other at Anfield and the kids have grown up together. We have been through a lot together, highs and lows, good times and bad times.
"To be able to call him a team-mate but also a friend — and he’s been a close friend of mine — it’s an absolute privilege.
"He’s been amazing for the club and amazing for the changing room. He’s decided to move on and it will be a big farewell, that’s for sure."
On the prospect of ever playing against each other, Robertson joked: "We wanted a game together, we wanted Scotland to play Egypt.
"We always joked if I was at left-back and he was on the wing we’d be up against each other.
"We both have the same passion playing for our countries, we’ve had a lot of conversations about playing for our national teams."