The Heroes star, 21, has been dating the Russian sportsman, 35, since 2009 but they have now revealed the relationship is over.
Panettiere confirmed the news in a statement, obtained by Germany’s Bunte.de, while the boxer has blamed the split on their struggle to maintain a long-distance relationship.
Panettiere’s statement reads, “While we decided to split, we feel great sympathy and respect for each other and will surely stay close friends.”
Klitschko adds, “We had a great time together. But more and more we realised how difficult it is to maintain a relationship when living on two continents… I cherish Hayden as a person and woman. I’m sure we will stay friends.”
Panettiere previously dated her Heroes co-star Milo Ventimiglia. They split in early 2009.