Throughout his career, Weber has represented Canada at several international ice hockey tournaments. His first experience with Hockey Canada came for the national junior team, when, on December 22, 2004, he was named to the roster for the 2005 World Junior Ice Hockey Championships in Grand Forks, North Dakota. There, his play with Dion Phaneuf formed the team's top defensive pair, helping Canada win its first junior gold medal since the 1997 tournament. Despite being held pointless throughout the tournament, Weber finished tied for third among plus-minus leaders with a rating of +10.