In October and November of 1966, there was an uptick in terrorist activities stemming from Syria and Jordan. Furthermore, Syrian artillery consistently targeted kibbutzim (collective settlements) situated beneath the Golan Heights. In April 1967, Israel retaliated by launching an aerial assault on Syrian positions in the Golan Heights. On April 7, an air battle ensued in which Israel shot down six Syrian aircraft. Subsequent to this incident, the Israeli government cautioned that it would undertake further actions if Syrian-backed terrorism persisted. In response, the Soviets fed the Egyptians false intelligence, alleging that Israel was amassing troops for an assault on Syria. Despite Israeli refutations and confirmations of their innocence by U.N. ground observers, Egypt remained wary.

By May 14th, while Israel marked its Independence Day, Egypt had its armed forces on high alert and began relocating them to the Sinai. In reaction, Israel initiated a partial call-up of its reserves.

On May 16th, the head of the Egyptian armed forces, General Muhammad Fawzi, penned a letter to the United Nations Emergency Forces Commander, seeking the removal of U.N. forces from the border. Subsequently, on May 18th, Egyptian Foreign Minister Mahmoud Riad asked the U.N. to evacuate all its troops from Egyptian territories, including the Gaza Strip. U.N. Secretary-General U-Thant concurred and proceeded with the withdrawal. In the meantime, Israel intensified its reservist call-up.

On May 22nd, Egyptian President Nasser declared the Gulf of Aqaba closed to all Israeli vessels, provocatively stating, “The Jews threaten war; we tell them we are ready for war.”

The next day, Israeli Prime Minister Levi Eshkol labeled the straits' closure a breach of international law and an act of aggression against Israel. Concurrently, US President Johnson articulated, “The United States regards the Gulf as an international waterway, and believes a blockade against Israeli shipping is illegal and could seriously undermine peace. The right to free passage in international waterways is a fundamental interest of the global community." Nevertheless, a UN Security Council resolution condemning the blockade was thwarted by a Soviet veto.

While this was transpiring, the US endeavored to assemble an international flotilla to reopen the Straits of Tiran. Regrettably, most countries refrained from participating, compelling the US to abandon the initiative.

On May 28th, after Abba Eban returned from the US, the Israeli cabinet held an extended session. Contemplating whether to grant the US more time or approve a preemptive strike, the cabinet leaned towards patience. This was a challenging decision, especially as Israel's prolonged army mobilization was unsustainable. With memories of the Eichmann trial still fresh and fears of another Holocaust rising, Eshkol's subsequent speech, emphasizing diplomacy, was poorly received, inciting calls for a new government.

On May 29th, Nasser proclaimed, "Today, the matter isn't about Aqaba, the Straits of Tiran, or UNEF. It's about the rights of the Palestinian people and the 1948 aggression against them. We demand complete rights for the people of Palestine."

On May 30th, King Hussein of Jordan arrived in Cairo and entered into a defense pact with Egypt, effectively placing Jordanian troops under Egypt's command in the event of a conflict.

By June 1, a new Israeli government was formed that integrated opposition parties, with Moshe Dayan assuming the role of Defense Minister. The prevailing sentiment was clear: the US couldn't assemble a viable international initiative, but it would understand if Israel decided to act.