Who is Zayn Malik's best friend in One Direction?

Zayn said in his statement when leaving 1D "I know I have four friends for life in Louis, Liam, Harry and Niall. I know they will continue to be the best band in the world"

Now, I'd presume that's the order of closeness he has with them and Louis is the closest .. ?

Louis is the closest to Zayn. They are always together these days.

Louis is

All of the guys in 1D. I wish he wasn't leaving, I was sobbing all day 2day in school & last night. It's 2 much!!!

I'm thing Niall Horan because kinda have the same blood type

Louis Is Because He Is Closer To Zayn And Zayn Is Louis Brother In One Direction I Love Louis So Much He Is In My Heart And Zayn Like Brother To Louis Look At The Picture Down Below❤️❤️