Defense Minister Ehud Barak said Wednesday that a limited amount of fuel and humanitarian aid would be allowed into the Gaza Strip on Thursday.

Israel kept its border crossings with the Gaza Strip closed for nearly a week due to a rash of violence that erupted following a deadly Israel Defense Forces raid on Gaza and days of responsive Qassam rockets onto the western Negev.

It allowed some fuel shipments into the territory on Tuesday but food and other humanitarian supplies have yet to be transferred.

Following consultations with security officials, Barak said the fuel situation in Gaza shouls be evaluated on a day-to-day basis. He ordered the defense establishment to permit entry into the Gaza Strip for 30 trucks carrying humanitarian aid from international organizations.

A spokesman for the United Nations Relief and Works Agency on Wednesday said that Israel's long-term economic blockade on the Gaza Strip had a directly negative effect on the functioning of the world body's efforts.

"This has become a blockade against the United Nations itself," UNRWA spokesman Christopher Gunness said, citing a long list of supplies, including food., which have yet to be delivered.

The UNRWA, which provides food and other essentials to Palestinians in Gaza, said it will be forced to suspend food distribution to 750,000 Gazan residents on Thursday night unless supplies were allowed in.

A UN flour warehouse in Gaza City was empty Wednesday, and another held six tons of canned meat - three tons short of the amount required for a day's distribution, the UN said.

The UNRWA announcement came hours after Israel Defense Forces soldiers killed four Hamas gunmen apparently laying explosives near the Gaza border.

Following the attacks, a number of mortar shells were fired at the western Negev. No injuries or damages were reported.