Thousands of Palestinians in Gaza City held a rally on Friday in solidarity with an Islamic Jihad member, detained without trial by Israel, on the 62th day of a hunger strike.

"We stand by the heroic symbol of prisoners, brother Khader Adnan, in his unlimited hunger strike," head of the Hamas government in Gaza Ismail Haniya, just back from a tour of Gulf countries via Egypt, told reporters ahead of the event.

Palestinian officials say Adnan's two-month hunger strike is the longest period a Palestinian detainee or prisoner has ever gone without food.

The procession, attended by all Palestinian movements, began at the Al-Omari mosque after Friday prayers and ended at the headquarters of the Red Cross.

"In his hunger strike, Khader Adnan is not fighting for a personal cause, but for the defence of thousands of prisoners," a Gaza leader of Islamic Jihad, Nafez Azzam said in a speech.

This Friday's weekly demonstration in the West Bank village of Bilin, marking the seventh anniversary of rallies against the Israeli separation barrier, was also dedicated to Adnan. An AFP correspondent said it was joined by some 1,000 demonstrators.

Adnan, a 34-year-old baker, was arrested by Israel on December 17 near the West Bank city of Jenin, where he had been spokesman for Islamic Jihad. He has been held since without being charged under a procedure known as administrative detention.

He began refusing food a day after his arrest and is now said to be close to death.

His lawyer filed a petition to Israel's Supreme Court, two days after an Israeli military court rejected an earlier appeal by Adnan to have the four-month administrative detention order lifted.

Following a recent examination of the prisoner, an Israeli NGO on Wednesday expressed grave concern about his well-being.

"Khader Adnan is in immediate danger of death," Physicians for Human Rights-Israel said in a statement.

"A fast in excess of 70 days does not permit survival," it said. "Infusion of liquids, adjustment of salts and the addition of glucose and vitamins cannot prevent certain death."

Human rights groups in Israel and overseas have appealed to Israel to free him or put him on trial.

Under Israeli law, a military tribunal can order an individual held without charge for up to six months at a time. Such orders can be extended by further six-month periods indefinitely, if approved in a new court session.