Border crossings with Gaza were reopened a day after Israel closed them in response to a Palestinian mortar attack on Monday that strained a truce reached between the parties.
The border crossings at Karni, Sufa and Nahal Oz were reopened on Wednesday morning. Apart from essential supplies, Palestinians in Gaza are expecting to receive supplies of cement for the first time this year.
The six-month truce between Israel and Hamas-led militants came into force on June 19 after Egypt was involved in mediating a ceasefire between the two sides. The deal is limited to the Gaza Strip.
Under the agreement, Israel was to gradually abolish economic sanctions imposed on Gaza, and the sides were to continue negotiations on the release of the kidnapped Israeli soldier Gilad Shalit, who has been held captive in Gaza for two years.
Israeli Prime Minister Ehud Olmert earlier said the ceasefire would be "very short."
