An Israeli military court has extended the detention without charge of three prisoners including an MP with the Islamist Hamas movement, the Palestinian Prisoners' Club and Hamas officials told AFP on Sunday.

Prisoners' Club spokesman Amani Sarahne named another of the prisoners as Hossam Khader, a former MP with the ruling Fatah movement of Palestinian president Mahmud Abbas.

"The court refused his appeal yesterday because the military prosecutor decided to renew his administrative detention order for another six months," she told AFP, saying he had already spent a year being held without charge.

Administrative detention is an antiquated procedure dating back to the British Mandate under which military courts can hold suspects without charge for periods of up to six months, which can be renewed indefinitely.

The other two prisoners were both members of the Hamas movement which rules Gaza, a Hamas official in the West Bank told AFP on condition of anonymity.

One was Hamas MP Mohammed al-Natshe, whose year-long administrative detention was extended by another four months, and the second was Hussein Abu Kweik.

It was not immediately clear how long Abu Kweik's latest period of detention was, and how much time he had already spent behind bars.

The Israeli army could not immediately confirm the reports.

Last month, more than 1,500 Palestinian prisoners began a mass hunger strike, with most protesting against the conditions of their detention. A smaller group of six prisoners went between for seven and 11 weeks without food in protest at being held without charge.

On May 14, the prisoners agreed to end their strike after hammering out a deal with Israel in exchange for a package of measures.

Israel also agreed to release all administrative detainees at the end of their current detention periods, unless further evidence against them emerged.

Khader did not take part in the mass hunger strike, and it was not immediately clear whether the other two had.