RAMALLAH, Palestinian Territories — Hamas prisoners being held in Israeli jails on Monday began a hunger strike to protest after seven of their number were put in solitary confinement, a minister told AFP.

Issa Qaraqa, the Palestinian minister for prisoner affairs, confirmed a 24-hour hunger strike had begun during the morning but could not confirm how many of the 2,800 Hamas inmates were observing it.

The strike was called a day after Israel moved seven prisoners from the Islamist movement's political leadership into solitary confinement, he said.

"(Israeli Prime Minister Benjamin) Netanyahu wants to put pressure on the Hamas leadership over Shalit," he told AFP, referring to an Israeli soldier who was captured by militants on June 25 2006 and is still being held in Gaza.

"This is naive," Qaraqa said.

German-brokered talks to negotiate a prisoner swap ground to a halt at the end of 2009 over the terms of the deal, which would see Gilad Shalit freed in exchange for 1,000 Palestinians prisoners -- 450 with blood on their hands.

The move to isolate the prisoners came just days after Netanyahu said he was going to cut the privileges enjoyed by Hamas prisoners in light of Shalit's ongoing captivity and Hamas's consistent refusal to let him be seen by the International Committee of the Red Cross.

In Gaza City, about 500 people held a rally in support of the striking prisoners which was organised by the enclave's Hamas rulers along with members of the Islamic Jihad movement.

"Hamas prisoners in Israel jails have begun a one-day hunger strike against the new policy of isolating our prisoners in Israeli jails," said Fader Abu Karish, head of Waed, a support group for Hamas prisoners.