Joaquin PhoenixJoaquin PhoenixWalk The Line star Joaquin Phoenix is rumoured to be more than just friends with his latest co-star. 

He is currently filming movie We Own The Night with hottie Eva Mendes in New York and the pair have been spotted out on the town.

Eva, who starred in Hitch and has dated Matt Damon, is currently said to be in a relationship with filmmaker George Gargurevich.

According to the New York Daily News, Joaquin and screen beauty Eva were spied having an "intimate dinner" this week.

The New York Post reported onlookers saying: "They were absolutely adorable together."

Apparently they then headed off to hotspot Club Butter in Manhattan for more 'romantic' behaviour.

Eva MendesEva MendesThe newspaper quotes a source as saying:

"They held hands and danced together. It was weird - everyone knows she has a longtime boyfriend."

Eva's spokeswoman has denied any hint of a romance, insisting that "they are just good friends".

Maybe they are... can't a couple of work pals go for dinner and a dance?

Then again, we are dealing with the fickle world of celebrity here.

For now, we are keeping an open mind.