LONDON/DUBAI - Iran has begun talks with Japanese companies under a U.S. sanctions waiver allowing it to resume oil sales, though prospective buyers are seeking a longer waiver and reassurances about ship safety, three Iranian and Western sources said.The waiver, ​part of 60-day peace talks between Tehran and Washington, was issued on June 22 and ‌expires Aug. ‌21.Three Japanese buyers were looking at possible crude oil purchases from Iran, ​their first since 2019, said two Iranian sources, who declined to be identified due to the sensitivity of the issue.