By Adam Entous
JERUSALEM, June 24 (Reuters) - Israel will use small border passages to bring basic supplies into the Hamas-held Gaza Strip, leaving the main Karni crossing that is the territory's economic lifeline closed for security reasons, officials said on Sunday.
Instead of reopening Karni as the United Nations and other aid groups had hoped, Israel will allow around 3,000 tonnes of emergency food and medicine to enter the Gaza Strip through the much smaller Kerem Shalom and Sufa passages five days per week.
Israel believes this amount will be enough to avert a humanitarian crisis in the impoverished coastal strip.
Some aid groups said the plan may head off a food shortage, but cautioned that the closure of Karni would cripple the moribund Gaza economy. Karni is the only functioning passage for Palestinian exports from the territory of 1.5 million people.
Oxfam International Director Jeremy Hobbs said Karni's closure could cause a health disaster by preventing companies from bringing in water treatment equipment and chemicals.
Israel wants to isolate Hamas economically, diplomatically and militarily in the Gaza Strip, where the Islamist group seized control more than a week ago, while allowing funds and goods to flow to President Mahmoud Abbas's emergency administration in the occupied West Bank.
The vast concrete and steel border post at Karni, Gaza's entry and exit point for virtually all goods, was a centrepiece of U.S. efforts to revive the long-stalled peace process after Israel pulled out of the strip two years ago.
Citing security concerns and Israel's policy of boycotting Hamas, an official with Israel's Airports Authority, which oversees the crossings, said, "We don't see any reason at the moment to open Karni".
Under the Israeli aid plan, 3,000 tonnes of food and medicine -- the equivalent of 100 truckloads -- will enter through Kerem Shalom and Sufa every Sunday to Thursday. On Fridays, 1,500 tonnes of supplies will cross into Gaza through Kerem Shalom.
"That's what we, together with the international organisations, understand the Gaza Strip needs. In case they need more, we will transfer more," the official said.
Israel controls the land crossings between Gaza and Israel, as well as Gaza's air space and territorial waters. Israel does not allow the crossing of people or goods by sea or air.