Scott Maslen found it "really hard" to film kissing scenes with Samantha Womack.
The 'EastEnders' actor - who plays Jack Branning on the BBC One soap - has admitted on-screen smooches with his former co-star (Ronnie Mitchell) were tough because he has been friends with her "for so long".
He said: "I've known Sam for so long it's ridiculous, she's very dear to me.
"That was actually a real hard thing coming in as an actor, because I've always worked with people that I don't know.
"It's easier in a way when you don't know them.
"You have to play against all the other stuff if it's your mate, you've got to go, 'Oh!'
"When we kissed we were both like, 'Oh god!' "
Scott also revealed his pal Samantha and her on-screen sister Rita Simons (Roxy Mitchell) used to gang up on him to play pranks - and the pair once hid a jacket potato with tuna under his bed for "weeks".
Speaking on Monday's (03.08.20) upcoming edition of 'EastEnders: Secrets from the Square', he adds: "They'd leave things under my bed, like jacket potato with tuna in it, for days, weeks.
"Rita would come over and go, 'Have you not found it yet?' I'd say, 'What are you talking about?' 'The jacket potato with the tuna!'
She's gone under my bed and pulled it out.
"It sounds like we're puerile but we can then go from that to this really depressing [storylines]."
Scott will appear on the 'EastEnders' spin-off show alongside his on-screen brother Jake Wood (Max Branning), who recently admitted he loves shooting fighting scenes with his pal.
He said: "We laugh a lot and hopefully that will come across in 'Secrets From The Square'. The first couple of years, Max and Jack were fighting a lot. They were at loggerheads. Obviously Jack was with Tanya for a short time, who was the love of Max's life so that didn't go down too well with Max.
"Every five minutes they seem to be throwing punches at each other at the Vic. They were just fun to do, these big epic fights. I think over the years the characters have just been there for each other. At their lowest points, they've been there to support each other no matter how much they fight. To me it seems like a very real sibling relationship."
Tagged in Scott Maslen Jake Wood