BANGKOK (AP) — The United States says it will not be able to carry out a major climate study this year because Thailand has delayed a decision on whether to grant the U.S. space agency permission to use a key naval air base.

NASA’s request to use Thailand’s U-Tapao air base as the project’s operations center has faced opposition from critics who say it could be a cover for military purposes. The base is located in Chonburi province, 190 kilometers (118 miles) southeast of Bangkok.