The separation was "amicable", according to a source, who revealed to E!: "They spent a lot of time apart because of work, and it was difficult on their relationship."
The pair, who dated for several years after meeting on the set of X-Men: First Class, split in 2012 but reunited in 2013.
Nicholas Hoult and Jennifer Lawrence
Jennifer recently spoke of their relationship and the trust they have in each other while on set.
"When we're busy, we agree to mutually ignore each other. Not completely, but neither of us gets mad when the other doesn't text back or call. Life's super busy. Obviously you know what they're doing, and you trust them", she told Marie Claire magazine.
Nick also recently gushed about their relationship, admitting: "It’s fun because in this business you are away from one another for long periods of time", he told V magazine.
"So when you’re on set together it’s a brilliant thing, because you actually get to spend time together."
Nick is currently in Tokyo filming a new sci-fi drama called Equals.
He took a break from filming on Thursday for a lunch date with his co-starKristen Stewart at Daiwa in the world-famous Tsukiji Fish Market.