The Israeli military says it has made contact with a French yacht carrying pro-Palestinian activists trying to breach Israel's naval blockade of the Gaza Strip.

The military said it contacted the Dignity al-Karama on Tuesday and warned the vessel the leave the area.

The yacht is the only vessel remaining from a flotilla that pro-Palestinian activists had hoped to launch from Greece last month. It left Greek waters Sunday with 16 people on board.

The military said it notified the ship that any supplies on board could be transferred legally to Gaza through an Israeli port and existing land crossings.

The activists say the naval blockade of Gaza is an illegal act of punishment against the more than one million Palestinian residents of the impoverished territory.

Israeli officials have vowed to maintain the blockade to prevent arms from reaching Hamas militants who run Gaza. Israel also says it is meeting the humanitarian needs of Gazans by allowing daily deliveries of aid, fuel and consumer goods across its land border with the territory.