Osaka Mayor Toru Hashimoto's proposal for an adjacent city's airport to host training flights involving Okinawa-based U.S. Marine Corps MV-22 Osprey aircraft would require local consent, Defense Minister Itsunori Onodera told reporters Tuesday.

"It is important to see (first) if there is really consent from the local government, especially in relation to the residents," Onodera told a news conference, referring to the outspoken Hashimoto's proposal Monday for using the airport in Yao, Osaka Prefecture.

After Hashimoto made the proposal, Yao Mayor Seita Tanaka was quick to oppose the plan, citing safety reasons.