Canberra - Australia's Aboriginal leaders criticised the Prime Minister, Mr John Howard, yesterday for not issuing an official apology over past treatment of Aboriginal people, saying they would campaign for 100 years if necessary. Mr Howard's coalition will officially respond on Tuesday to a landmark "stolen generation" report into the past policy of forcibly removing Aboriginal children from their parents. However, it has been widely reported that the government does not intend to offer a formal apology.