Key members of the ruling coalition agreed in a meeting to change the name during the current session of parliament, which ends June 19. The main opposition Democratic Party has already offered support.

Hirohito's April 29 birthday was a major holiday during Japan's conquest of Asia when the emperor was regarded as divine. After Japan surrendered in 1945, the April 29 holiday was preserved but renamed Greenery Day.

The bill before parliament will rename it Showa Day, using the posthumous name of Hirohito, who died at age 87 in 1989 after watching his country defeated in war but rise again as an economic superpower.

Asked about concerns that "Showa Day" could be linked to Japan's past militarism, Chief Cabinet Secretary Hiroyuki Hosoda said: "If a majority approve the revision while acknowledging such a fact, that's the Diet's (parliament's) will."

Prime Minister Junichiro Koizumi, asked separately about the bill's expected passage, told reporters: "That's lawmaker-initiated legislation. I will leave the discussion to them."

Under the legislation, May 4 -- a holiday with no name during Japan's "Golden Week" of holidays -- would be named Greenery Day.

Opinion remains divided on Hirohito. Many Japanese see him as a benign figure out of touch with a militarist cabinet and military, rejecting the view of foreign scholars who believe he was intimately involved in war planning.

An earlier attempt to change the holiday's name to Showa Day failed in the face of strong opposition by the left.

Japan has gradually been accepting more outright displays of nationalism.

In 1999 it recognized the "Hinomaru" rising sun flag as the official flag and the "Kimigayo," which praises the emperor, as the national anthem, despite criticism from liberals.

On Wednesday Tokyo authorities disciplined some 50 high school teachers who refused to stand up and sing the national anthem at graduation ceremonies as required since 2003 by the nationalist-led municipal government.