By Jonathan Marcus
Diplomatic correspondent, BBC News
Israel seems surprised at the scale of the power shortages in Gaza
Even before Israel began to implement its decision to restrict fuel supplies to the Gaza Strip there was strong international condemnation from the United Nations, from aid organisations, and indeed from a number of friendly governments.
This pressure is now likely to intensify.
The European Union's External Relations Commissioner Benita Ferrero-Waldner has already called for the restrictions to be lifted; though there is every sign that Israel's Prime Minister Ehud Olmert intends to stand firm.
As the rocket fire from Gaza has increased in intensity over the past 10 days so the fuel restrictions have begun to bite. Already difficult living conditions in Gaza are being made worse.
Hamas is warning of a humanitarian collapse; many Palestinians believe that the rocket fire has simply prompted a collective punishment directed against all of Gaza's residents.
Israel argues that if restrictions are to be lifted then there is a simple answer; the rocket fire should be halted. But the Israelis also seem surprised at the scale of the power shortages in Gaza.
Doing nothing is not an option for the Israeli leadership. But a full-scale re-invasion of Gaza is also ruled out, at least for now
They argue that about three-quarters of the electricity used there comes from either the Israeli or Egyptian power grids and this electricity is still flowing.
Gaza's plight has already provoked outrage in much of the Arab world with the television station al-Jazeera already devoting considerable programming to the crisis.
Egypt is threatening to open crossing points into the Gaza Strip if Israel does not relent.
'Israel at war'
The Israelis seem to be suggesting that it is Hamas which is manipulating the power supply to increase the suffering to win propaganda points.
GAZA'S ELECTRICITY SOURCES
Gaza uses 187 megawatts of electricity
Israel supplies 64% of this, and Egypt 9%
The remaining 27% is produced by Gaza's power station
Israel supplies the fuel oil for the Gaza power station
Source: UN report on Gaza's electricity use, May 2007
Equally it is far from clear whether the power grid in Gaza is sufficiently modern or flexible enough to be able to mitigate the shortages prompted by the Israeli-imposed restrictions on fuel for the power station there.
Israel considers itself to be at war with Hamas in the Gaza Strip. Rocket fire into southern Israel has continued ever since Israel's withdrawal from the territory.
But in recent weeks the barrages have increased in intensity; physical casualties have been few, but the psychological pressure of living under the daily threat of attack has made ordinary life in the south very difficult. In turn this has brought huge pressure on the Olmert government to act.
Doing nothing is not an option for the Israeli leadership.
But a full-scale re-invasion of Gaza is also ruled out, at least for now.
Israeli military commanders fear that this could lead to considerable Israeli casualties quite apart from a bloody death toll among Palestinian civilians if troops were forced to assault densely-populated urban areas.
Such a move would also leave open the question of what Israel would do if it re-captured the territory?
So for the moment Mr Olmert has chosen a middle way; tightening economic restrictions, increasing the intensity of Israeli military operations inside the Gaza Strip, and stepping up the targeted killings of Palestinian militant leaders.
This too is inevitably leading to Palestinian civilian casualties.
Israel clearly hopes that the suffering in Gaza will lead to pressure on Hamas to stop the rocket attacks. But in reality it may only serve to increase the pressure on Israel to lift its restrictions as a humanitarian crisis beckons.