They had a trade embargo, denial of bunkering facilities, increased port security, and control procedure on transshipment, technical data, and customs inspection. The U.S. also used diplomatic means to frustrate Cuban trade negotiations in Israel, Jordan, Iran, Greece, and possibly Japan.[2] From the outset, Lansdale and fellow members of the SG-A identified internal support for an anti-Castro movement to be the most important aspect of the operation. American organization and support for anti-Castro forces in Cuba was seen as key, which expanded American involvement from what had mostly been economic and military assistance of rebel forces.