Kristen Stewart has hit back at reports she is dating her Twilight co-star Robert Pattinson in real life.

The 19-year-old has been constantly linked to Pattinson, 23, since they began shooting the vampire saga last year.

But she told Entertainment Weekly that she refuses to speak about the speculation because she wants to keep her private life private.

“I probably would’ve answered it if people hadn’t made such a big deal about it,” she said. “But I’m not going to give the fiending an answer.”

However, Stewart, who was being interview alongside Pattinson and their fellow co-star Taylor Lautner, admitted there was little she could say to quash the rumours.

“I’ve thought about this a lot. There’s no answer that’s not going to tip you one way or the other,” she said.

“Think about every hypothetical situation: ‘Okay, we are. We aren’t. I’m a lesbian.’  I’m just trying to keep something.”

Stewart added: “If people started asking me if I was dating Taylor, I’d be like ‘F**k off!’ I would answer the exact same way.”

The actress is currently appearing alongside Lautner on the South American leg of the promotional tour for The Twilight Saga: New Moon.

Pattinson, meanwhile, is meeting fans of the film in Japan ahead of its release on November 20.

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