Sancho played in all three matches in which Trinidad and Tobago took part in the 2006 FIFA World Cup, thus becoming the first former St. John's player and first current Gillingham player ever to play in a World Cup. In the third match, against Paraguay, he scored an own goal and defeat in this game confirmed Trinidad and Tobago's elimination from the tournament.
On 9 October 2006, Sancho announced his retirement from international football along with 12 others. Speaking at a press conference, Sancho said: "It's not just monetary. They have made certain contractual arrangements which they have now reneged on." This followed a dispute between the World Cup players and the Trinidad and Tobago Football Federation regarding bonuses for playing in the World Cup. The issue went to court in the United Kingdom which ruled in favour of the players. Several of the players subsequently returned to the national team, but Sancho did not play for T&T after the 2006 World Cup. As of February 2015, the legal dispute between the players and the national association was still ongoing.