The British-based rights group said the firing of rockets by Palestinian militants -- which the Israeli military says has dropped by about 90 per cent since its offensive in Gaza last year -- did not justify the sanctions.
"The blockade does not target armed groups but rather punishes Gaza's entire population by restricting the entry of food, medical supplies, educational equipment and building materials," said Malcolm Smart, the group's Middle East and North Africa director, in a statement.
"The blockade constitutes collective punishment under international law and must be lifted immediately."
Amnesty said Egypt was partly to blame because it only occasionally opens its Rafah crossing with Gaza -- the only terminal bypassing Israel.
It also faulted Cairo for starting work on an underground border wall in a bid to halt the smuggling tunnels that have become an economic lifeline to the territory but are also used by Hamas to smuggle in weapons and money.
"However, as the occupying power, it is Israel that bears the foremost responsibility for ensuring the welfare of the inhabitants of Gaza," Amnesty said.
Monday is the one-year anniversary of the mutual ceasefires that ended the 22-day Gaza war, which killed some 1,400 Palestinians and flattened entire neighbourhoods. Thirteen Israelis were killed during the fighting.
Israel imposed strict sanctions on Gaza in 2006 following the capture of an Israeli soldier by Hamas and other militants in a deadly cross-border raid.
It tightened the blockade when Hamas -- which is pledged to Israel's destruction -- seized power in June 2007 after a week of street battles with forces loyal to the Western-backed Palestinian president Mahmud Abbas.
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