Israel has announced that its navy will attempt to stop Canadian and Irish boats carrying pro-Palestinian activists bound for the Gaza Strip. The Canadian boat "Tahrir" and the Irish boat "MV Saoirse" left the port of Fethiye in southwest Turkey on Wednesday after Turkish authorities gave them permission to sail to the Greek island of Rhodes. The Israeli military spokesman''s office said the country''s navy was "prepared to contact" the vessels and had "completed the necessary preparations in order to prevent them from reaching the Gaza Strip". Lieutenant-Colonel Avital Leibovich, an Israeli military official, would not say how the boats might be stopped, saying only "we will have to assess and see if we are facing violent passengers." Describing their journey as a "provocation", she said Israel would offer to unload any aid supplies on board and deliver them to Gaza. Sailing under the flag of the Comoros Islands, the Tahrir is carrying six activists, a captain and five journalists. The Saoirse - sailing under the US flag - has 12 Irish nationals on board, none of whom are journalists. It will take at least a couple of days before the boats reach the Palestinian waters of the Gaza Strip, where they expect to be approached by the Israeli navy. The activists say the new attempt the break the siege on the Gaza Strip is part of a campaign they call "freedom waves", implying that more such efforts will follow. Both ships were part of previous attempts to break the siege on the Gaza Strip that was stalled when the Greek government refused to let a flotilla leave from its shores in July this year.