Ruby Rose "knew" she was still in love with Jess Origliasso as soon as she saw her.

Ruby Rose

Ruby Rose

The 'Orange is the New Black' star initially dated the Veronicas singer in 2008, and they rekindled their romance when the 30-year-old actress offered to write, direct and appear in the group's new music video for 'On Your Side'.

And it didn't take long for Ruby to realise she was still in love with her former flame.

She said: "Probably the second I saw her [I knew]

"It definitely wasn't planned. it just came out of nowhere. and it was a really delightful thing to happen."

And Ruby's romance has been given the seal of approval by her close friend Taylor Swift.

She told news.com.au: "I talk to her [Taylor] about everything and everyone."

The Australian actress can next be seen in 'xXx Return of Xander Cage' and she had a great time working alongside Vin Diesel, who plays the titular character in the action saga.

She gushed: "Vin is everything.

"He's the softest ... he's like a teddy bear. I knew that doing the film with him would be an exceptional amount of fun, but I didn't realise how much fun.

"It was beyond expectations. I'm like, that's not really a job!"

Ruby got her big break playing Stella Carlin in Netflix series 'Orange Is The New Black' and admits she was intimidated when she first joined the popular show as she was such a big fan of the programme.

She said: "I was definitely nervous because everyone was so familiar to me, and yet of course I didn't know them.

"I was wondering if I'd be the outcast, but they were just the best teachers in everything."

And though she spent years trying to land a job in Los Angeles before securing her breakthrough role, Ruby doesn't mind people thinking of her as an overnight success as her stardom even seemed sudden to her.

She said: "It doesn't annoy me -- to the majority of the world, it must have felt like that.

"I wasn't anywhere on their radar ... and then 'Orange' came out, and I was everywhere.

"To have my first role be such a big one, and on such an enormous TV show, and to be so well-received. Even I was like, 'did that just happen?!'"