Canadian activists are heading home after a failing to deliver an aid shipment to the blockaded Gaza strip.

The Canadians aboard the Tahrir announced their decision Saturday after authorities prevented the ship from leaving a port in Greece.

The vessel was part of a flotilla hoping to break the Israeli blockade of the Gaza strip.

Organizer David Heap says the group still succeeded in drawing attention to the conditions in Gaza.

Greece cited safety concerns when stopping the vessels from leaving port, but organizers say it was pressure from Israel that blocked the flotilla.

The Harper government has been critical of the flotilla with Foreign Minister John Baird calling its mission "provocative" and "unhelpful."

A similar flotilla last year ended in bloodshed — nine people were killed and 45 injured after Israeli soldiers boarded a Turkish vessel trying to break the blockade.