Mori made the comments about the emperor and Japan on Monday night at a meeting of lawmakers and Shinto religious leaders in Tokyo.
``We hope the Japanese people acknowledge that Japan is a divine nation centering on the emperor,'' Mori said. ``Education reform led by regional (Shinto) guardian deities and shrines should be carried out."
The comments stirred controversy in Japan and elsewhere in Asia, where many people have bitter memories of Japan's World War II military aggression carried out in the name of a deified emperor.
"The Japanese side should learn a lesson from history, especially during World War II, to prevent history from repeating itself," Chinese Foreign Ministry spokeswoman Zhang Qiyue told a news conference. "We hope the Japanese side can seriously and responsibly handle the historical problems concerned and not do anything to hurt the feelings of the Chinese and other Asian peoples."
Japan Communist Party chief Tetsuzo Fuwa said he "cannot contain my surprise" over the remarks.
"The idea of 'divine Japan' made people believe Japan is a special country entitled to conquer the world and became the spiritual driving force behind the nation's militarism and aggression," Fuwa said in a statement.
In Shintoism, Japan's native religion, the emperor is believed to be directly descended from the gods who gave birth to the Japanese islands. The late Emperor Hirohito was worshipped as a living god during the war.
Shinto became the national religion in the 19th century, which regarded the emperor as a living god. Japan then took the road of aggression in Asia under the name of the deified emperor.
Religion and state functions were separated under the U.S.-drafted post-World War II constitution. The emperor is now defined as "the symbol of the state" without any powers over the government, and statements harking back to the days of deification have been considered a political taboo.
Defenders of Japan's current constitutional also attacked Mori's statement.
Yukio Hatoyama, head of the main opposition Democratic Party, sharply criticized Mori over the remarks, a newspaper reported Tuesday.
Hatoyama said they were based on thinking embodied in Japan's former constitution and denied the ``people's sovereignty,'' the Mainichi Shimbun said.
On Tuesday, Mori said the comments were made in the context of Japan's history and culture and had nothing to do with the nation's political system.
``The comments do not contradict the postwar principle that sovereignty rests with the people,'' he told reporters.
In March, Mori angered many people in the southern state of Okinawa by saying that teachers there opposed the government's new policy requiring the national anthem at functions because they were ``controlled by communists.''