UN rights officials investigating Israel's deadly raid on a Gaza-bound aid flotilla wrapped up their hearings in Jordan after interviewing a total of 30 witnesses, one of the flotilla organisers says.

The three experts "listened to the testimony of 25 Jordanians from among the 33 who were on board the Mavi Marmara," whose assault by Israeli commandos sparked clashes in which nine Turks were killed, Jordanian Maissara Malass said.

Malass, a trade union activist, said three Israeli Arabs, including MP Hanin Zoabi, and two Lebanese had also been interviewed in Jordan.

"We do not have any illusions about the report (coming to anything) because it will undoubtedly be professional but, as always, the problem will be in its application," he said.

Zoabi, who was aboard the Mavi Marmara, told the inquiry on Tuesday the Israeli commandos had a "licence to kill."

"I told the UN investigators in Amman that the Israeli attack was violent from the start and that the Israelis had a clear licence to kill, and they did not even try to avoid the bloodshed," the Israeli MP told AFP.

"I sensed that the investigators were serious about the probe. They asked clear questions and I gave them clear answers. I stressed that the Israeli commandos wanted to kill the activists, who were unarmed,"" she added.

Israel says its naval commandos only resorted to force after being attacked as they reached the deck of the ferry, but the activists insist the soldiers started firing first.

Zoabi sparked outrage in Israel for taking part in the flotilla.

In July, the Israeli parliament voted to strip Zoabi of her diplomatic passport and parliamentary funding for legal defence.

The UN team arrived in Amman last Sunday. It is to report back to the UN Human Rights Council at its next session on September 13-October 11.

The three experts mandated by the UN rights council have already interviewed unspecified witnesses in London and Geneva, and have met the Turkish and Israeli ambassadors in Geneva.

Israeli officials have rejected the council's mission as biased.