"A detachment of Islamic state fighters executed yesterday's London attack," a statement posted on Amaq's media page, monitored in Cairo, said.
Three attackers rammed a van into pedestrians on London Bridge and stabbed others nearby on Saturday night before police shot them dead.
It was the third militant attack in Britain in less than three months.
ISIL, losing territory in Syria and Iraq to an offensive backed by a US-led coalition, had sent out a call on messaging service Telegram early on Saturday urging its followers to carry out attacks with trucks, knives and guns against "Crusaders" during the Muslim holy month of Ramadan.
Islamist militants, or people claiming allegiance to the group, have carried out scores of deadly attacks in Europe, the Middle East, Africa, Asia and the United States over the past two years.
(Source: Reuters)
