An announcement by an Arab Israeli lawmaker that he plans to join a pro-Palestinian flotilla seeking to break Israel's blockade on Gaza caused outrage Monday among the country's political class.

Basel Ghattas, an MP with the Joint Arab List, sparked controversy after he announced he would join other parliamentarians and public figures from around the world in the latest attempt to reach Gaza by ship later this month.

Gaza has been subjected to an Israeli blockade for nine years, which includes a complete ban on ships entering or leaving the coastal enclave's waters.

Pro-Palestinian activists have repeatedly tried to reach the Hamas-run Gaza Strip by sea but have been blocked by the Israeli navy.

In May 2010, Israeli commandos staged a botched raid on a six-ship flotilla which ended in bloodshed that claimed the lives of 10 Turkish nationals and sparked a crisis with Ankara.

Hanin Zuabi, a female Arab-Israeli MP who was on board at the time, was roundly denounced by the Israeli political establishment as a traitor -- with Ghattas now facing a similar outcry.

"It is the gravest thing possible that an Israeli MP would join the flotilla whose aim is to help the Hamas terror organisation," said Immigration Minister Zeev Elkin from the ruling rightwing Likud party.

"Israeli law does not allow anyone to serve in parliament who supports a terror organisation," he railed in an interview with army radio.

Deputy foreign minster Tzipi Hotovely said that joining the attempt to run the blockade was evidence Ghattas was working against Israel.

"The participation of an Arab Israeli MP alongside those who want to fight against Israel is a demonstration of activity in the service of the enemy under the sponsorship of parliamentary immunity," she said in a statement late Sunday.

She said the foreign ministry had been working around the clock to prevent the flotilla from reaching Israel's territorial waters.

One of the boats involved in the bid is a Swedish trawler called "Marianne of Gothenburg" which set sail from Sicily on Friday evening.
It is expected to meet up with several other vessels in the coming days to form what is being referred to as the Freedom Flotilla III, organisers say.

They are expected to try and reach Gaza before the end of the month.