"I am heartbroken, not only due to the senseless deaths of so many innocent victims, including many young people, but also because of the alleged reasoning behind these heinous acts," the American sporting icon wrote in a letter published by the VG daily.
"Fears of multiculturalism demonstrate a lack of understanding of the commonality that exists among people across ethnic, racial and religious lines," added the former three-time world heavyweight champion.
Muhammad Ali, now 69 and suffering from Parkinson`s disease, is himself a convert to Islam, the religion reviled by Anders Behring Breivik, who has confessed carrying out the attacks which he called part of a "crusade" against a "Muslim invasion" of Europe.
The 32-year-old rightwing extremist first bombed government offices in Oslo, killing eight people, before going on a shooting rampage on the nearby island of Utoeya where the ruling Labour Party was holding a youth summer camp, killing another 69 people, most of them teenagers.(*)
Editor: Heru Purwanto
Copyright © ANTARA 2011