The Palestinian Islamist group Hamas ruling Gaza said on Tuesday is to begin deducting the previously optional "zakat," or alms, from firms and individuals during Ramadan.
The Zakat Foundation created by Hamas will begin deducting the money during the Muslim holy fasting month that begins on Thursday or Friday "from the taxes on firms," its chief Rami al-Khatib told AFP.
"This will begin as an optional measure before becoming obligatory," he said, adding that the authorities would strive "not to increase the amounts" to be deducted from individuals.
Khatib said the aim was to "collect funds for zakat and distribute it to the poor."
In the West Bank, the rival Palestinian Authority's religious affairs minister Mahmud Habbash said the decision was illegal.
"We warn citizens against this because it's illegal," he told a news conference in the town of Ramallah. "What's dangerous is that they want to oblige people to pay zakat and that's illegal and raises many doubts."
The move amounted to "a threat for zakat funds," he said.