Israel deliberately brought the Gaza Strip’s infrastructure to the brink of collapse before its military offensive in the enclave in December and January and has since blocked any efforts of its rehabilitation as part of a strategy to defy Hamas, a report by an Israeli rights group claimed this week.

The damage to the impoverished Strip’s electricity network has prompted the company that distributes Gaza’s electricity this week to warn the 1.5 million residents that it will be forced to institute power cuts of up to 10 hours a day, five days a week, according to Tel Aviv-based Gisha, a group that advocates for Palestinian rights.

The group said such cuts would be the worst in the territory in at least six months and would hit especially hard in Gaza City and its surroundings, where key institutions such as Shifa Hospital are located.

Sari Bashi, executive director of Gisha, said: “Israel has deliberately drained Gaza of the fuel and supplies needed to maintain the water, sewage and electricity systems as part of a policy to pressure Hamas. Israel calls it economic warfare, we call it collective punishment.”

Israel launched its military campaign in Gaza in December, claiming it aimed to curtail rocket attacks on its southern communities by militants from Hamas, an Islamic group which controls Gaza, and other factions. Gaza health officials and local rights groups have said that more than 1,400 people were killed in the assault.

Israel controls all of Gaza’s border crossings except for Rafah, which is managed by Egypt. Israel also has authority over most of Gaza’s power supply, with an Israeli electricity company providing about half of the region’s power and Gaza’s own power station relying on Israel granting it access to industrial diesel.

Ahead of Israel’s recent attacks, the country brought Gaza’s infrastructure to a “weakened state”, the report said. Its restrictions on the supply of fuel, spare parts and building materials such as concrete and cement were tightened in 2007, when militants of Hamas violently took over the enclave by routing forces loyal to Fatah, a rival secular Palestinian movement that holds sway over the occupied West Bank.

Furthermore, the blockade on the coastal territory intensified after Israel’s shaky, six-month-old ceasefire agreement with Hamas, which included an easing of restrictions, broke down in November 2008 and the country almost completely closed off Gaza’s borders.

The nearly two-year-old blockade prompted a humanitarian predicament for many Gazans once the operation began in December, Gisha said.

It added: “At the height of the [fighting], more than half a million residents were cut off from running water, sewage flowed in the streets, and hospitals were left to operate on generators running 24 hours a day. All this took place while the strip was being bombarded from the air, sea and land, and its borders remained sealed, leaving residents with nowhere to run.”

Indeed, the restrictions have prompted daily power cuts, frequent disruptions to the water supply, tens of millions of litres of raw sewage being dumped into the sea and contaminating the groundwater that serve much of Gazans’ drinking needs, as well as the reliance of hospitals on decrepit generators.

The group claimed that more than six months following Israel’s assault, the country is still blocking efforts to repair the electricity, water and sanitation systems.

Gaza’s electricity system, for example, “urgently” needs 400 types of spare items such as transformers, power poles and electrical cables that are either completely missing from its inventory or available in limited amounts, Gisha said. Israel has for months been holding up more than 30,000 such parts in warehouses within its territory or in the West Bank, refusing to grant them permits to enter Gaza, the group added. As a result, some 10 per cent of Gazans have been completely disconnected from electricity since the onslaught.

The water system is not faring any better. The shortage of spare parts for its repair has resulted in 10,000 Gazans being deprived of running water since the attacks ended and another 100,000 residents having access only once every five to seven days, according to the report.

Gisha cites Khaider Abu Daher, a 34-year-old father of five in Gaza, who said the destruction of his home during the fighting has prompted his family to live in a tent since then, walk 1.5km twice a day to fetch water as well as scramble to gather wood on which it cooks meals.

The report suggested that Israel’s High Court of Justice colluded with the state’s destruction of the infrastructure by giving it a stamp of approval. According to Gisha, the three petitions it submitted along with other rights groups against Israel’s policies from October 2007 to January 2009 were all rejected. It said that the court accepted Israel’s justifications of its restrictions without holding a “serious discussion” to determine the country’s obligations towards Gazans.

Gisha added: “The rejection of the petitions and acceptance of the state’s claims, time and again, effectively legitimised the state’s policies and exposed the limitations of the High Court in reviewing the activities of the military in the occupied territories.”