According to the NHK broadcaster, the defenсe minister told reporters that the work had been temporarily halted following a request from Okinawa's authorities, who called the work "illegal" because the prefecture's defense bureau had failed to provide them with the required documents.
Iwaya also expressed hope that the suspension would not prevent the land reclamation work from starting as planned.
According to media reports, full-scale reclamation is expected to begin on December 14.
The plans to relocate the US airbase sparked protests among tens of thousands of local residents demanding that the facility be removed from Okinawa completely, and not just moved to another location.
Okinawa, which accounts for a small fraction of Japan's territory, hosts 74 percent of US military facilities and more than half of all US forces deployed in Japan.