Trump was speaking alongside Fifa president Gianni Infantino at the signing of an executive order to establish a taskforce that will oversee preparations for the tournament.
Trump will chair the task force, which will “co-ordinate with federal agencies in planning, organising and executing” the tournament.
Forty-eight teams will compete in the expanded World Cup in 2026.
Eleven of the 16 host cities are in the United States, with Toronto and Vancouver in Canada also set to stage matches, as will Guadalajara, Mexico City and Monterrey in Mexico.
Azteca Stadium in Mexico City will host the opening match on 11 June with the final being played at MetLife Stadium in New Jersey on 19 July.
The United States will also host the 2025 Club World Cup in June and July.
