Diego Luna was ''nervous'' about ''getting too excited'' when he filmed his first sex scene.

The 'Rogue One: A Star Wars Story' actor says he was just 12-years-old when he had to film an intimate scene on a television show and was very scared about having ''40 people'' watching him.

Speaking on 'Conan Without Borders: Made in Mexico', he said: ''I arrived, I was very nervous and I was just like, 'I hope she likes it and after the scene, because I know it's not going to be sex, but then something can start from there.'

''And then I get there and I see 40 people looking at me with the camera - s**t. And all I could just think of was, 'Oh, I don't want to have a hard [on], please, please, please. I don't want to get too excited.' And obviously it didn't happen. I was 12, I couldn't control it. She was very nice; she hid it.''

It comes after Diego recently revealed he nearly missed a casting call for the role of Captain Cassian Andor because he thought it was just a ''drunken cousin'' calling him.

He said: ''I saw this British number calling me at 2 a.m., and I have family in England, so I thought it was, like, a drunken cousin from a bar or something.

''I ran over and saw that it was [director] Gareth Edwards wanting to give me some news! I just jumped around like crazy - it was quite a special day. [Edwards] said, 'Okay, welcome to Star Wars.'''

However, he was forced to keep it a secret for a ''long time''.

He added: ''I didn't trust my children to keep the secret because, well, they're kids! I told them we were spending the summer in England, but I couldn't tell them why for quite a long time.''