Gaza/Tel Aviv - Palestinians living in the Gaza Strip have become world champions in improvisation. After three weeks of near-total closure of the enclave, they juggle to get by.

Conditions had been gradually improving five months into a June 19 truce, brokered by Egypt between Israel and the radical Islamic Hamas movement ruling the Gaza Strip.

Israel had somewhat eased the economic blockade it first imposed several years ago in response to rocket attacks by Gaza militants at its southern towns and villages.

But a November 4 clash between Israeli soldiers and Hamas fighters near the Gaza border reversed the cautious progress made.

Israel responded to a new wave of rocket attacks by all but completely shutting its border crossings, opening them only three times in the past 22 days to three truck convoys carrying basic humanitarian supplies and to a limited supply of industrial diesel for Gaza's power plant.

Abu Nael Ghabaien sighs as he points at the items missing on the shelves of the supermarket he owns in Gaza City: Dairy products, frozen meat, fruit, cleaning materials, diapers.

Goods are brought in via the thriving network of tunnels dug by smugglers under the Gaza border with Egypt, but these are often non- basic supplies, such as chocolates, cigarettes and soft drinks, he explains.

When Israel briefly opened its border crossing of Kerem Shalom with southern Gaza to a shipment of basic goods on Monday, "I requested several missing things, but I only got a few boxes of yoghurt and they have run out now, as you can see," Ghabaien says.

With basic goods such as rice, flower, cooking oil, coffee, tea, locally grown vegetables and canned goods being the only products that are not scarce in Gaza along with the more luxury goods smuggled in via Egypt, many Gazans live largely on a non-voluntary vegan diet these days.

Not only are milk products hard to come by, but locally-produced meat, largely the only kind available, has become expensive amid the lack of import of cattle.

Ironically, the smuggling from Egypt has made certain items such as cigarettes and diesel cheaper than in Israel. A pack of Marlboro costs around 6 Israeli shekels (about 1.50 dollars) in the Gaza Strip, less than a third its price in Israel.

Smuggled diesel costs under three shekels a litre in Gaza, compared to nine shekels for diesel sold in Israel.

But the catch is that Egyptian-bought diesel is of low quality. Many car-owners in Gaza, where most vehicles run on diesel - still buy the Israeli kind, which is more expensive, but less likely to cause car trouble, residents say.

Lengthy power cuts have also again become a common feature, especially in Gaza City and the north of the enclave. During the truce, Gaza's only power plant received 2.2 million litres of European-sponsored industrial diesel a week, enabling it to produce some 55 megawatts, or nearly 30 per cent of Gaza's needs.

Electricity lines from Israel continue to supply some 60 per cent and Egypt the remaining 10 per cent. But that amount has now been reduced and electricity is again being rationed.

"We are chasing the electricity from house to house," says one Gaza resident, who says his house receives electricity for only 12 hours every 24 hours.

On Wednesday night, when the electricity in his building was due to be cut at 9.00 pm, he and his wife raced home from a late trip to a market to catch the elevator still working. They were late and his wife, in her ninth month of pregnancy, had to take the stairs to their apartment on the fifth floor, he recounts.

Gazans also have to plan basic activities such as showers around the rationed power supplies.

For lack of cooking gas and during the on-and-off power blackouts, many use the Egyptian-smuggled diesel to light lamps and stoves, sometimes mixing it with salt to make it "lighter," and leaving behind a filthy smell and smoke.

Bakery owner Mohammed al-Kholi says that for the past three weeks he has stopped making pastries and baguettes and now produces mainly regular Arab pita bread.

Sometimes the bread comes out immature when the electricity suddenly goes off, he says, explaining it takes time to get the oven going again on his emergency generator, which also runs on diesel.

"I keep monitoring the timetables of the power," he says. "Sometimes we open the shop in the middle of the night to take advantage of the electricity as much as possible."