Laharrague made his international "début" in a match during the 2005 Six Nations Championship, in a match against Wales on 26 February. He played in the subsequent matches against Ireland in Dublin and Italy in Rome. He made another five appearances for France that year, playing in test matches against the Springboks, Australia, Canada and Tonga. He did not play in the 2006 Six Nations Championship, but was selected for the mid-year tests against Romania and the Springboks.