The couple of three years are on a break after struggling with long-distance dating, PEOPLE magazine reports. Currently, Andrew is filming in Taiwan.
RELATED: Emma and Andrew's cutest PDA moments
"He's thrown himself in the project to the detriment of all else," the source told the magazine. "But it's too early to say the relationship is over."
"Emma understands his work anxieties - it's why she originally pulled out of 'Cabaret' last year and only did it this year - but they're taking a break from seeing each other," the source said. "They're both a slave to their schedules. This time last year they were privately discussing marriage."
While Andrew films in Asia, Emma has been spending time with family in Los Angeles. The source, however, isn't willing to write them off as a couple just yet.
"It's one of those situations where only Andrew and Emma quite know if they'll pick up where they left off or they've separated," the source says.
RELATED: Hollywood's hottest redheads
Meanwhile, the magazine also quotes a separate source who said the duo hasn't officially broken up.
"They are just separated for work," the second source says. "Andrew is overseas. They are both busy with their careers and have not seen each other."
The two haven't been photographed since early January, and Andrew was noticeably absent while Emma attended the Golden Globes and Academy Awards for her work on "Birdman."