Jennifer Aniston and Justin Theroux are "very happy together".

The couple started dating earlier this year and are absolutely smitten with each other, according to Jennifer's 'Just Go With It' co-star Ben Stiller.

Ben told Us Weekly: "They seem to be really happy together. They're both great people. I love them both."

Ben's actress wife Christine Taylor added: "They're both just very cool, terrific people."

Although she is very happy with Justin, Jennifer, 42, has insisted claims that she is pregnant and set to wed Justin are all false.

Jennifer - who was previously married to Hollywood heartthrob Brad Pitt - revealed: "Rumour number one: I am not planning to get married any time soon. I've been married once, and I don't know if I'll get married again. But I can tell you that as of this very moment, I have no plan to get married. Got that?"

"And rumour number two: No, we're not pregnant. It's just I quit smoking, so I've gained a couple of pounds."