Israeli Air Force aircraft Wednesday dropped leaflets urging Palestinians to leave a buffer zone in the northern Gaza Strip by 6 p.m. (1600 GMT) or face Israeli gunfire from across the border.
Meanwhile, Israeli commanders handed Palestinian National Authority (PNA) security officials maps delineating the zones prohibited for Palestinian entry.
"The new restrictions will remain in power until further notice, " the Israeli army said.
Palestinian militants, mainly from the Islamic Jihad, have frequently fired Qassam rockets from northern Gaza since Israel finished Gaza pullout in September.
In recent weeks, the homemade rockets hit several strategic facilities in southern Israel, including a power plant in Ashkelon.
Therefore, Israel decided to enforce a buffer zone in northern Gaza to halt rocket attacks.