The Israeli military said on Saturday that it would observe what it called "a humanitarian window in the Gaza Strip" for 12 hours from 8:00 am (0500 GMT).
Displaced Palestinian children are pictured on July 25, 2014 at a United Nations (UN) school in Jabalia in the northern Gaza Strip
An army statement said that Gazans who had previously been warned by the military to vacate their homes due to planned attacks should "refrain from returning" and said forces would retaliate if attacked or if militants were to fire rockets into Israel.
It added that under the agreement the army would continue to destroy militants' tunnels in areas of the Gaza Strip under its control.
Hamas said earlier that it and other militant groups in Gaza had reached "national consensus on a humanitarian truce".
A statement from the Hamas-run interior ministry in Gaza warned people not to approach bombed-out buildings and militant bases for fear of "explosive objects".