ARISH, Egypt, Jan 6 (Reuters & JMCC) - Members of a convoy seeking to enter Gaza Wednesday will be allowed to enter if they leave some 60 private cars behind, a reporter for the satellite channel al-Jazeera reports.

Turkey brokered the arrangement after Egyptian security forces clashed on Wednesday morning with members of a convoy led by left-wing British politician George Galloway trying to take relief supplies to Palestinians in the Gaza strip.

Turkey has said that it will ensure the goods carried in tens of private vehicles will make their way into Gaza and to residents there.

A Reuters correspondent in the port city of Arish, 40 km (25 miles) from Egypt's border with Gaza, saw security forces throwing stones at about 520 people travelling with the convoy.

The protestors were holding four members of the Arish harbour police while security forces detained seven members of the convoy, who have been locked in a dispute with Egyptian authorities over the route of the 198 trucks.

Police used water cannon to force the protestors to leave Arish harbour, which they had occupied, a security source said. Around 40 members of the convoy had minor injuries while around 15 police officials were hurt, witnesses said. Cairo insists the food and other supplies should go to Gaza via an Israeli-controlled checkpoint while the convoy's leaders want to use the Egyptian-controlled Rafah border crossing.

Egyptian authorities wanted 55 of the trucks to go to the Israeli checkpoint, said Galloway, the sole member of the British parliament for the Respect party who has long campaigned for the Palestinian cause.

We refused this, he told Reuters TV. It is completely unconscionable that 25 percent of our convoy should go to Israel and never arrive in Gaza. Because nothing that ever goes to Israel, ever arrives in Gaza.

Cairo has imposed strict regulations and restrictions on pro-Palestinian foreign activists who have held protests in Egypt since late December to mark the first anniversary of Israel's three-week offensive on the Hamas-ruled Gaza Strip.

It has also controlled the movement of Palestinians and some foreigners at Rafah and is building a controversial steel wall along its border with Gaza to prevent smuggling.

Alhamy Aref, a local government official in North Sinai, was trying to negotiate a deal between the two sides on releasing the detained people, the Reuters correspondent reported.

Leaders of the convoy originally refused Egypt's condition that the aid should be shipped via Arish on the Mediterranean rather than via the Red Sea port of Nuweiba. But they later relented and started arriving at Arish on Thursday. (Reporting by Yusri Mohamed; Writing by Yasmine Saleh; editing by David Stamp)