Argentine Football Association (AFA) spokesman Jose Luis Meiszner said Japan had been given 10 days to review their initial decision to concentrate on the country's recovery from last month's devastating earthquake and tsunami.
"There is a deadline of 10 days," Copa America organising committee chief Meiszner told a news conference at the AFA's Buenos Aires offices.
"Nothing has been settled. We met, we talked and we set a deadline to see if Japan gets to the Copa America," he said after a meeting between AFA president Julio Grondona and his Japanese counterpart Junji Ogura.
Ogura, whose country had accepted an invitation to play in the tournament for the second time, told South American Football Confederation president Nicolas Leoz at their Asuncion headquarters on Monday that Japan wanted to withdraw.
Nearly 28,000 people are dead or missing and thousands have been left homeless as a result of the magnitude 9.0 earthquake and massive tsunami that hit Japan's northeast coast. Sports schedules are in chaos including the J-League football competition.
Japan, who played as a guest team at the 1999 Copa in Paraguay, were drawn in Group A with Argentina, Bolivia and Colombia.
World champions Spain said earlier on Tuesday they had been invited to fill the gap left by Japan in the 12-team tournament while another option was a CONCACAF country filling in.
Costa Rica, who have played in the tournament three times and are coached by Argentine Ricardo La Volpe, are considered favourites to come in.
