Following the continued closure, the secretary-general reiterated his appeal on Friday but to no avail.
Karen AbuZayd, commissioner-general for the U.N.'s Relief and Works Agency (UNRWA), which supports Palestinian refugees, warned that a humanitarian "catastrophe" loomed if Israel continued to prevent aid from reaching Gaza.
"It's been closed for so much longer than ever before. We have nothing in our warehouses. It will be a catastrophe if this persists; a disaster," said AbuZayd.
AbuZayd added that the human toll of this month's closure of the territories was "the gravest since the early days of the second intifada or Palestinian uprising.
This began in October 2000 after former Israeli premier Ariel Sharon paid a controversial visit to al-Aqsa Mosque in Jerusalem, Islam's third holiest shrine. Sharon was warned by Israeli security that this could provoke political unrest but went ahead nevertheless.
Israel closed Gaza's borders after a barrage of rockets were fired from Gaza at Israeli towns bordering the territory. These were in response to a cross-border military incursion by the Israeli Defense Forces (IDF) into Gaza on Nov. 4 which broke the fragile five-month ceasefire between Hamas and Israel and killed a number of Palestinian fighters.
In the vicious and bloody cycle of attack and counter-attack more than 20 Palestinians have been killed while two Israelis have been lightly injured.
Less humanitarian aid has reached Gaza during this ceasefire than during the first part of 2006 when Israel was subject to far heavier attacks.
During that time the Palestinian Authority (PA) ruled Gaza in a unity government with the Islamic resistance organization Hamas. Today Hamas controls the territory.
In return for Hamas respecting the current truce, which it has largely observed although there have been periodic breaches by both sides, Israel was obliged to significantly ease the closure. To date this has not occurred.
Half of Gaza's population of 1.5 million people depends on aid from UNRWA for survival. John Ging, UNRWA's Gaza director, said that 20,000 Gazans needed rations on a daily basis.
"Normally we have stock in our warehouses to tide over emergency periods and days of closure but we have now run out completely. Last week alone 60,000 people went without food," Ging told the Middle East Times.
Israel briefly opened the borders for a few hours and allowed 30 trucks of aid in last Monday following intense international and diplomatic pressure. However, only 11 of those trucks were for UNRWA.
"Furthermore, a minimum of 10 trucks a day are required just to maintain normal supplies of aid and those 30 trucks' supplies only lasted several days against a shortfall of 19 days," added Ging.
To try and meet the shortfall, over the weekend Gaza's bakeries began grounding second-rate wheat, usually fed to farm animals and birds, to replace the depleted reserves.
Furthermore, Gaza's main power plant was forced to shut down last week thereby causing 70 percent of Gaza's residents to go without electricity. Hospitals were forced to suspend emergency operations due to fuel shortages and a lack of spare parts for hospital machinery.
The coastal territory also ran out of cooking gas and so Gazans resorted to the dwindling supplies of electricity for cooking, further increasing the load on the collapsing electricity plant.
Meanwhile, Gaza's Coastal Municipalities Water Utility (CMWU) has pumped hundreds of tons of untreated sewage into the ocean during the course of the last few weeks as there is insufficient fuel to operate the water treatment plant.
This had heightened the risk of disease spreading due to contaminated water leaking back into Gaza's underground water supply. Additionally Gaza's health ministry has run out of over 300 essential medicines as Israel bans the imports of these.
AbuZayd expressed concern about the rising rates of malnutrition, especially anemia amongst children. Due to the closure, chronic poverty, unemployment and lack of nutritious food and clean drinking water, Gazans are not getting a balanced diet.
"There is a chronic anemia problem. There are signs that it's increasing. What we are beginning to notice is what we call stunting of children, which means they are not eating well enough to be bigger than their parents," AbuZayd stated.