Prime Minister Yoshiro Mori needs to further explain the intention behind his comment that Japan is a "divine nation centering on the Emperor" to win the public's understanding, Chief Cabinet Secretary Mikio Aoki said Monday.

"(The prime minister) holds the responsibility of telling the public clearly of the intentions (behind the remark)" at some time, Aoki told a regular press conference.

The top government spokesman did not specify when he thinks Mori should explain his remarks.

Meanwhile, although opposition party leaders want Mori to participate in a one-on-one Diet debate over the issue, as of Monday the matter of whether to hold a debate session this week remained undecided.

The ruling bloc, led by the Liberal Democratic Party, has stubbornly refused to let the debate session proceed this week, saying the main opposition Democratic Party of Japan was rude Thursday when Mori tried to win its acceptance of the timing of the upcoming general elections during a meeting with DPJ head Yukio Hatoyama.

Hatoyama refused to take a seat and left after handing the prime minister a written request for his Cabinet to resign en masse over the controversial remark.

Since the "divine nation" comment, the DPJ has criticized Mori as lacking the aptitude to be prime minister.