Japan lodged a complaint with Beijing after China drilled the Tianwaitian gas field in the East China Sea, Reuters reported, citing a story in Japanese newspaper the Sankei. In a statement on the website of the Foreign Ministry, Beijing dismissed the complaint, stating the area in question does not lie in disputed waters. In June, Japan and China signed a agreement to jointly develop the gas field and share profits in disputed areas in the East China Sea. The field has known reserves of 92 million barrels of oil equivalent, and may have larger unknown reserves. The Sankei reported China may have already finished development of the field and entered the production stage.