“Petra Nemcova and Jamie Belman confirm their separation,” a rep for Nemcova tells PEOPLE. “They remain close friends and thank their families for their continued support during this time.”
“There will be no further comment on the matter,” the rep added.
Nemcova, 32, and Belman, 28, announced their engagement in January 2011.
Nemcova was previously engaged to photographer Simon Atlee, who was killed in the 2004 Asian tsunami disaster.