Organizers of a flotilla planning to challenge Israel's sea blockade of the Gaza Strip say they will sail within the next few days. They called on Greek authorities to let them depart despite mounting diplomatic pressure from the Israeli government.

In Athens Monday, a loose coalition of activist groups said Greece was putting up “administrative obstacles” in response to pressure from Israel and other countries.

Several hundred pro-Palestinian activists – many from Europe, Canada and the United States – plan to board up to ten ships for a journey across the Mediterranean Sea to Gaza.

Israel's security cabinet Monday ordered the country's military to prevent the convoy from reaching Gaza but to avoid clashes with activists on board. Senior ministers also instructed Israeli diplomats to continue their efforts to prevent the flotilla from setting sail to the Palestinian territory.

Israel also dropped its threat to ban journalists from the country for 10 years if they were found on the flotilla. The head of the Israeli government press office had said in a letter to journalists that the convoy is organized by Western and Islamic extremists, and that those taking part would be in violation of Israeli law.

Journalists say they should be allowed to cover a legitimate news story.

Also Monday, an Israeli military spokeswoman said new intelligence reports reveal that extremists participating in the flotilla have supplies of what she called “dangerous incendiary chemicals” to use against Israeli forces.

Military officials also claim that some activists have said they want to kill Israeli soldiers and that two participants have connections to the militant Islamist group Hamas.

Flotilla organizers say as many as 10 ships will carry humanitarian goods and hundreds of pro-Palestinian activists to Gaza, which is controlled by Hamas. It is not clear when the ships will set sail, but organizers have said it could begin this week.

The effort will also commemorate the flotilla effort broken up by Israel in May of last year.

Israeli commandos killed nine Turkish activists, including one with dual U.S. citizenship, when troops stormed a Turkish vessel that was part of a flotilla trying to break the Gaza blockade.

The Turkish aid organization IHH, which was involved in last year's effort, said several of its activists will join the ships sailing for Gaza. But the group dropped plans to send its own vessel, the Mavi Marmara, again this year.