Israel said last week it would reduce electricity supplies to the Gaza Strip after the Palestinian Authority (PA), which is pressing Hamas to relinquish control of the enclave seized in 2007, limited how much it pays for power to the area.
The decision was expected to shorten by 45 minutes the daily average of four hours of power that Gaza's 2 million residents receive from an electricity grid dependent on Israeli supplies, the officials said.
Separately, a Palestinian official, who spoke on condition of anonymity, said on Sunday that Cairo had agreed in talks last week with a Hamas delegation to sell the group fuel to get the Gaza Strip's sole power station back online.
He said Hamas's newly elected Gaza leader, Yehya al-Sinwar, had met in Cairo with Egyptian officials and discussed securing the frontier with Egypt's Sinai peninsula, where Islamist State fighters have killed hundreds of policemen and soldiers.
Egypt has accused Hamas of aiding the militants, an allegation the group denies, and has kept its border crossing with the Gaza Strip largely closed.