Chief Cabinet Secretary,Yasuo Fukuda said Japan planned to send troops before the end of the year, although Prime Minister, Junichiro Koizumi, remained more cautious.
"We are firm in our thinking that we will have a dispatch (of troops) this year," Fukuda told a news conference, denying media reports that Tokyo might push back the dispatch until next year because of feared casualties and a domestic outcry.
"While taking security into consideration, we believe that there are areas where we can conduct reconstruction and humanitarian activities," Fukuda added.
Prime Minister Junichiro Koizumi, fresh from winning a Lower House majority in the weekend general election, told reporters on Wednesday that a dispatch within the year was possible "if the situation allows."
"I will look carefully at the situation and then decide," he said, amid media speculation that he is seeking to avoid a contentious debate in a short parliament session expected next week.
US Defence Secretary Rumsfeld is due to arrive in Japan on Friday and meet Defence Agency Director-General Shigeru Ishiba the next day.
Koizumi has promised President George Bush that Japan will send troops and provide largescale financial aid to Iraq.
"I will look carefully at the situation and then decide"
Prime Minister, Japan
The dispatch of an advance party of about 150 ground troops has widely been predicted to take place before the end of the year, possibly to Samawa in southern Iraq, followed by a main contingent of hundreds more in the new year.
About 300 navy personnel were also expected to transport vehicles and machinery aboard ships to the Gulf, while 150 air force troops would fly C-130 Hercules cargo planes between Baghdad, Basra and a base in Kuwait, the Asahi Shimbun said on Tuesday, citing a draft summary of the dispatch plan.
The mission, which would include less than 100 civilians, would help with water supplies, medicine, transport and education starting in mid-December, the daily said.
Fukuda said on Wednesday final preparations were still needed on the ground, hinting that the government would send another survey team before committing troops.
Under Japanese law, the prime minister has to seek parliamentary approval within 20 days of troops being sent or at the next parliamentary session if lawmakers are not sitting.