Blake Lively was worried 'Gossip Girl' producers wouldn't approve of her romance with Penn Badgley.

Blake Lively

Blake Lively

The 30-year-old star dated her co-star - who played her on-screen boyfriend Dan Humphrey in the show - during its first few seasons and she admits she was concerned their romance wouldn't go down well with the show's bosses.

She said: "Stepping back from it, I can see it. But I remember there was one point where we were just afraid of how our personal lives overlapping our work life could be perceived by our bosses. [But then] we were like, 'Oh no, that's exactly what they want.' They wanted us all to date. They wanted us all to wear the same clothes that we're wearing on the show. They wanted that, because then it fed their whole narrative. People could buy into this world."

And Blake - who is now married to actor Ryan Reynolds and shares daughters, James, two, and Ines, 11 months, with him - and Penn even managed to keep their real-life split from the show's executive producer Joshua Safran.

He added: "The shocking thing was, I found out on the set of the Season 2 finale that Blake and Penn had broken up months before. They kept the breakup hidden from the crew, which you could never do now.

"I don't even know how they did it. They kept it from everybody which is a testament to how good they are as actors. Because they did not want their personal drama to relate to the show."

Blake also confessed the lines were regularly blurred between herself and her character Serena.

She told Vanity Fair magazine: "At the time, I was wearing the same clothes and doing fashion shoots, and dating the same person that my character was dating - or sometimes that person [Dan] was my brother, you never know with Serena - and because of that, what people were projecting onto me was that I was Serena ... We look the same, and we acted the same as far as they could tell, because I wasn't doing anything but that show.

"If [Badgley and I] were photographed walking down the street, they didn't know if it was a paparazzi shot or if it was a shot from the show ... At the time, what was heightened was, wow, it all looks similar from the outside, but it's so different on the inside."