Prime Minister Eshkol traveled to the south of Israel on May 25 accompanied by Yigal Allon, Minister of Labor in his cabinet. General Ariel Sharon, who commanded Israel's troops in the south, told them that the developing situation presented a “historical opportunity” to destroy Egypt's army. Egypt could be attacked under circumstances that appeared defensive. Egypt's recent moves had indeed created such a possibility. “Nasser's exercise in brinkmanship,” wrote historian Roland Popp of the Cologne School of Journalism, “opened a window of opportunity in the eyes of the Israeli military leadership.” But Egypt's moves alone might not be accepted as sufficient for Israel to initiate a war, notwithstanding Israel's public position that the shipping restrictions constituted casus belli, legal cause for war. Allon suggested “inventing a pretext” to let Israel go to war, claiming that Egypt had initiated the hostilities. Israel would attack into Sinai and tell the major powers that Israel had just received information that Egypt was about to attack.

Eshkol stepped up his pitch that Egypt would soon attack. He sent Eban, who had by then arrived in Washington, an urgent telegram, instructing him to tell US officials that developments of the past few days had brought “a far-reaching change.” Egypt was reinforcing its troops in Sinai; Syria was concentrating troops along the border with Israel; Iraq, Kuwait, and Jordan were redeploying troops; and Egypt's minister of war was visiting Moscow. A few hours later, Eshkol sent a telegram to Ambassador Harman, asking him to tell President Johnson that Israel needed an immediate public declaration that an attack on Israel would be considered an attack on the United States. Eshkol anticipated Johnson declining, and then Israel would explain to Johnson that Israel must act alone. Israeli cabinet members pressed Rabin, as IDF Chief of Staff, to say whether Egypt was really about to attack. Rabin replied that he could not confirm an intent on Egypt's part to launch a general attack.