"I was relieved to learn about Yasuda’s [release]. We will confirm his identity as soon as possible," Abe told journalists on Wednesday.
Chief Cabinet Secretary Yoshihide Suga said at the press conference this would likely happen after 3 p.m. (6:00GMT).
In 2015, Daesh terrorists posted a video of the execution of Japanese journalist Kenji Goto. The Japanese reporter went to a Daesh-controlled area and fell into the hands of the terrorists because he intended to rescue another Japanese hostage Haruna Yukawa, who had reportedly disappeared earlier in Syria.
Syria has been in a state of conflict since 2011, with numerous opposition groups and militant and terrorist organizations fighting the Syrian Army in an attempt to topple the government of Bashar Assad. Russia, along with Turkey and Iran, is a guarantor of the ceasefire regime in Syria and has also been providing humanitarian aid to residents of the war-torn country.