Israel will launch a public campaign on Tuesday against a plan by the Turkish organization IHH and several left-wing European groups to send a flotilla to the Gaza Strip this May, a year after another IHH flotilla resulted in bloodshed that prompted widespread international condemnation of Israel.

IHH activists aboard that flotilla attacked Israeli soldiers who tried to intercept it with axes, knives and iron bars. Nine Turks were killed.

Open gallery view Turks greeting the return of the Mavi Marmara last month. Credit: AP

Deputy Foreign Minister Danny Ayalon will summon foreign ambassadors to the ministry today to seek their help in stopping this year's flotilla, which is slated to contain at least 15 ships. The sailing date has not yet been finalized, but the ministry expects it to be sometime between May 15, when the Palestinians commemorate the "Nakba" ("catastrophe" ) of Israel's establishment, and May 31, the anniversary of last year's deadly interception.

Thirty organizers from 15 countries met in Madrid about six weeks ago to discuss their plans, which have so far been kept under wraps for "security reasons." They also asked the governments of some of the countries whose nationals plan to be aboard the flotilla to guarantee their safety should Israel try to stop the ships.

Over the last two months, the Foreign Ministry has asked several governments, including those of Spain, Britain, Ireland and Sweden, to publish travel advisories warning their citizens against sailing to Gaza. Britain and Ireland have in fact done so.

When the president of Cyprus, Demetris Christofias, visited Israel about 10 days ago, the flotilla was a key topic of discussion. Christofias stressed that the order he issued a year ago banning ships from sailing to Gaza from Cypriot ports remains in force.

The ministry is far from sure the flotilla can be stopped by diplomatic means, but is determined to try.