A flotilla of eight ships carrying some 700 international activists and 10,000 tons of aid and construction materials is currently en route to the Gaza Strip from Turkey, in the most ambitious bid yet by pro-Palestinian groups to break Israel and Egypt's economic blockade of the territory.

But this effort, like previous ones, is likely to end in confrontation with Israel’s navy later this week.

Israel warned on Tuesday it is prepared to prevent the flotilla, which one official called “a provocation,” from reaching its destination in Hamas-run Gaza. Israel sealed its borders with the Gaza after Hamas, a bitter enemy, seized power there in 2007.

IN PICTURES: Palestinian smugglers on the Egypt Gaza border

But while a series of similar flotillas and aid convoys have managed to draw media attention to the now three-year-long Gaza blockade, which has devastated Gaza’s economy, they have so far failed to change Israel’s policy.

The most effective pressure currently may in fact be coming from within Israel itself. The Israeli rights group Gisha successfully took the government to court on May 6 over its Gaza policies.

Why is chocolate a security risk?

Gisha compelled Israel’s ministry of defense to reveal information about how it formally manages the blockade for the first time. After nearly three years of secrecy, government attorneys conceded the existence of an official defense ministry list of items approved for transfer into the enclave, as well as a “Red Lines” document that establishes minimum nutritional requirements for Gaza’s 1.5 million people.

Gisha had requested the government reveal on what basis it approves or rejects goods destined for the Gaza Strip, after items like chocolate, notebooks and jam were consistently barred without explanation.

Aid groups and local businessmen say there appears to be a whole-scale ban on construction materials, which Israel says armed Palestinian groups could use to build weapons, but the import of shoes and hairbrushes were approved only earlier this year. Coriander, ginger, and livestock remain off-limits, Gisha says.

“No one, not even businessmen or aid workers, are entitled to see a list of the products allowed into Gaza,” says Israeli economist, Shir Hever. “The only way to know if you can import something is if you try. It’s complete chaos.”

While the ministry refused to disclose the actual contents of the documents, claiming their details are harmful to national security and Israel’s relations with other countries, Gisha plans to press on, with the eventual goal of ending the blockade. The next hearing in the case is scheduled for October.

“This is not only essential to the Palestinians in Gaza, but that should also concern every citizen in Israel,” says Gisha’s spokeswoman, Keren Tamir. “There are major attempts by the government to hide information related to the blockade and, from our position in here, the first step to ending it is to expose this information in the name of democracy.”

Israel says that more than one million tons of humanitarian supplies have been allowed into Gaza since January 2009.

Meanwhile, four cargo ships and four passenger vessels have left several Mediterranean ports and plan to meet up in Cyprus on Friday, Greta Berlin, one of the organizers, told the Associated Press. From there, the group will embark on the one-day journey toward Gaza.

The cargo ships are carrying an array of donated goods not allowed into Gaza, including cement, prefab homes, lumber, window frames, paper for printing school books, children's toys, a full dentist's office, electric wheelchairs and high-end medical equipment, Ms. Berlin said.

IN PICTURES: Palestinian smugglers on the Egypt Gaza border

RELATED STORIES: