The couple, who recently ended their engagement, attended a party together and were spotted out at a French restaurant, then took a train back to London together, says a mutual friend of Law and Miller.
The pair, who have been on the rocks since Law admitted to having an affair with his children's nanny Daisy Wright, are still talking, the source says. "I think they are equally smitten with each other."
Still, the couple have not rekindled their engagement. "Their relationship is over. Jude is moving on," a source close to the actor confirms.
British media reported earlier this week that Miller had been seeing Law's friend, actor Daniel Craig, while Law was fighting to win her back.
But Craig and a spokesman for Miller deny the pair had a relationship, and a source close to Miller and Law tells PEOPLE that the rumors aren't true. "Her and Daniel Craig are very good friends and have been for a while ... It's all just too ridiculous for words."
After Law and Miller's latest bust up, he headed to Spain with a buddy, where he spent two nights lying low in Seville, while Miller was spotted lounging poolside at a Moroccan resort. It was after this time apart that the couple met in Paris.
As for Miller and Craig – who is expected to be named the new James Bond on Friday – the pair met two years ago while making the movie Layer Cake. This was also around the time that Law and Miller became friends on the set of Alfie.
"I'm going straight to my mum's place," Miller told the gathered photogs. "There's nothing going on between me and Daniel. We were in a movie together two years ago."