A Libyan-chartered ship carrying aid for Palestinians set a new course for Egypt on Wednesday after Israel's navy warned it away from the blockaded Gaza Strip, an Israeli official said.

The Moldovan-flagged Amalthea was heading to Egypt's El Arish port, the official said. There was no immediate comment from organizers of the aid ship.

The cargo vessel was absent from the real-time shipping map of MarineTraffic.com, suggesting that its GPS tracker was obstructed or turned off.

Egypt said late on Tuesday that the Amalthea had requested and been granted permission to dock in El Arish, and that authorities planned to transfer its declared haul of 2,000 tonnes of food and medicine overland to neighboring Gaza.

But the mission organizers, a charity chaired by Saif al-Islam Gaddafi - son of Libyan leader Muammar Gaddafi - insisted at the time that the ship would hold course to Gaza.

Israel had vowed to turn away or seize the ship - renamed 'Hope' by activists - rather than let it reach Gaza, whose Islamist Hamas rulers the Jewish state wants to keep isolated.

Yet the Israelis are mindful of international censure after their commandos killed nine Turks while boarding another Gaza-bound aid ship in Mediterranean high seas on May 31.

Earlier on Wednesday, Israeli officials said the navy was shadowing the ship in international waters 55 miles from Egypt and 80 miles from Gaza.

Israel Radio aired what it said was a recording of the ship's Cuban captain, Antonio, informing navy negotiators by radio that his engineers were trying to fix mechanical problems.

'It appears that the ship has overcome its difficulties. It is now heading to El Arish,' an Israeli official told Reuters.

The confusion over where and when the Amalthea would dock prompted an Israeli official to suggest there was disagreement between the hired crew of 12 and some 10 pro-Palestinian activists aboard determined to defy the Gaza blockade.

Israel Radio also aired what sounded like the navy warning the captain he would be held responsible for any showdown at sea. Other aid ships have been impounded in Israel, with some of their cargo eventually trucked to Gaza.

'You are in charge of the people on the ship, and any attempt to enter the area will be your fault only,' a voice that the radio identified as a navy negotiator is heard saying.

The Amalthea set sail from Greece on Saturday on a voyage that would ordinarily see it reach Gaza by Wednesday. Rerouting to El Arish would still require the ship to skirt Gaza.

Al-Jazeera satellite channel, which has a correspondent aboard the ship, said four Israeli warships were in pursuit.

Outcry at the bloodshed aboard the Turkish-flagged Mavi Marmara prompted Israel to ease overland trade with Gaza, but it kept the sea blockade, citing risk of arms shipments to Hamas.

'Both we and the Egyptians have a very great interest in ensuring that the Gaza Strip and Hamas do not stockpile weaponry and gain strength,' Deputy Israeli Foreign Minister Danny Ayalon said. Unlike Libya, Egypt has diplomatic relations with Israel.

On June 5, the navy commandeered the Irish-owned aid ship Rachel Corrie after it refused orders to turn back or dock in Israel for its cargo to be vetted for overland transfer to Gaza.

An Israeli inquiry by a military panel under a retired general into the navy's killing of the Turkish activists concluded on Monday there had been faults in planning the high seas interception but that lethal force was warranted.-Reuters