The actress, who plays Monica Geller in the show, wrote in an emotional Instagram post: "I am so grateful for every moment I had with you Matty and I miss you every day."

Perry, 54, died last month after an apparent drowning at his Los Angeles home.

Matt LeBlanc, who played Joey Tribbiani, said it was an "honour to share the stage with you and to call you my friend".

Also sharing a tribute on Instagram, LeBlanc wrote: "It is with a heavy heart I say goodbye. The times we had together are honestly among the favourite times of my life.

"It was an honour to share the stage with you and to call you my friend. I will always smile when I think of you and I'll never forget you. Never.

"Spread your wings and fly brother you're finally free. Much love.

"And I guess you're keeping the 20 bucks you owe me."

Cox shared what she described as one of her favourite moments with her friend "Matty".

"To give a little backstory, Chandler and Monica were supposed to have a one night fling in London. But because of the audience's reaction, it became the beginning of their love story.

"In this scene, before we started rolling, he whispered a funny line for me to say. He often did things like that. He was funny and he was kind."

Perry's death is being investigated by the Los Angeles County Medical Examiner's Office after a post-mortem examination with toxicology tests.

Perry was best known for playing wise-cracking Chandler Bing in Friends between 1994 and 2004. LeBlanc played Chandler's roommate and best friend Joey Tribbiani.

Friends stars LeBlanc, Cox, Jennifer Aniston, David Schwimmer and Lisa Kudrow, were among 20 mourners at Perry's funeral in the Hollywood Hills earlier this month.

In a joint statement released after his death on 28 October, the co-stars said: "We are all so utterly devastated by the loss of Matthew. We were more than just cast mates. We are a family.

"There is so much to say, but right now we're going to take a moment to grieve and process this unfathomable loss."

Read more:
What Perry's memoir revealed
Obituary: The one who made everyone laugh
Perry's life in pictures

Tributes poured in following Perry's death, including messages from Canadian Prime Minister Justin Trudeau - who attended the same school as the actor - and Sarah, Duchess of York, who had a cameo appearance in Friends.

Perry was open about his battle with substance abuse and addiction, and set up a sober living facility for men with similar issues.

A foundation has now been set up to help others struggling with the disease.

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The creators of Friends, Marta Kauffman and David Crane, said Perry was in a "really good place" when they spoke to him two weeks before his death.

Speaking to NBC's Today Show, Ms Kauffman said: "He was happy and chipper. He didn't seem weighed down by anything. He was in a really good place, which is why this seems so unfair."