Israel's Government Press Office issued a letter Sunday to foreign journalists, warning them that participating in the upcoming flotilla sailing to Gaza is illegal under Israeli law, and could result in anyone who joins the convoy being barred from Israel for up to 10 years.

The letter, signed by GPO director Oren Helman, states that the flotilla "is a dangerous provocation that is being organized by western and Islamic extremist elements to aid Hamas."

Helman asks editors to inform journalists that the Israel Defense Forces have been ordered to stop the convoy of ships from reaching Gaza, given that "The flotilla intends to knowingly violate the blockade that has been declared legally and is in accordance with all treaties and international law."

Furthermore, the letter says, "participation in the flotilla is an intentional violation of Israeli law and is liable to lead to participants being denied entry into the State of Israel for ten years, to the impoundment of their equipment and to additional sanctions."

Haaretz correspondent Amira Hass will be joining the flotilla, along with several dozen other journalists and several hundred activists from some 20 countries. Also joining the flotilla will be American writer Alice Walker, despite an American advisory that doing so could be a violation of U.S. law.

In May 2010, the Israel Navy boarded six boats that comprised a similar aiming to break the Israeli naval blockade on the Strip; nine activists on board were killed during the ensuing violence.