Israeli Prime Minister Benjamin Netanyahu speaks to the media at the southern Israeli port of Eilat on March 10 as Israel displayed rockets and other arms seized last week from a ship in the Red Sea. (Jack Guez/AFP/Getty Images)

Israel put on display here Monday a cache of long-range rockets and other artillery it seized last week from a shipment making its way up the Red Sea, allegedly destined for militant groups in the Gaza Strip.

Glistening in the sunshine at Israel’s largest naval base on the Red Sea were 40 M-302 surface-to-surface rockets with ranges of 50 to 100 miles, more than 181 mortar shells and about 400,000 rounds of ammunition, according to the Israeli military’s count.

The weapons, it said, had been concealed in large shipping containers with Iranian seals and hidden beneath bags of cement stamped “Made in the Islamic Republic of Iran” — proof, officials said, that the Iranians had sent the illicit cargo.

In an address to local and international news media gathered at the port, Israeli Prime Minister Benjamin Netanyahu said the rockets and other weapons on display were evidence that Iran could not be trusted.

“There are those who would prefer that we do not hold this news conference here today,” Netanyahu said. “They feel uncomfortable that we show what is really happening inside Iran. They prefer that we continue to nurture the illusion that Iran has changed direction.”

“We now have hard facts, and it’s important that the world gets this information,” he told reporters after the news conference.

The shipment, which Israeli naval commandos seized in a raid on the high seas near Eritrea last Wednesday, was unloaded in Eilat on Sunday. The weapons had been transported on a civilian vessel called the Klos-C, which Israeli military intelligence had been tracking for several months.

Jen Psaki, a spokeswoman for the U.S. State Department, confirmed last week that it, too, had been aware of the shipment. Netanyahu acknowledged the United States’ support and the close cooperation of its intelligence services in verifying the facts.

The carefully planned news conference Monday by Netanyahu comes as Catherine Ashton, the European Union’s foreign policy chief, is visiting Iran in an attempt to advance a program to curtail the country’s nuclear development.

During his speech, Netanyahu criticized Ashton’s outreach to the Iranians, saying: “We even saw representatives of the world powers shaking hands and smiling with the heads of Iran’s regime, at the same time we were unloading these missiles here in Eilat. By contrast, if we build some apartment or some balcony in a neighborhood of Jerusalem, we hear a chorus of vociferous international condemnations.”

At his weekly cabinet meeting in Jerusalem on Sunday, Netanyahu had called on Ashton to raise the issue of the illicit cargo with her Iranian hosts.

“I call this to the attention of Catherine Ashton, who is now visiting Tehran,” Netanyahu said. “I would like to ask her if she asked her Iranian hosts about this shipment of weapons for terrorist organizations, and if not, why not.”

A senior military intelligence official, who spoke on the condition of anonymity for security reasons, told The Washington Post that Israel had been tracking the shipment since it left its port of origin in Damascus, Syria, headed for Tehran. In Iran, the weapons were transported across land to the port of Bandar Abbas on the Persian Gulf. After a stop in Iraq, the shipment had been making its way to Sudan’s main port when Israeli naval forces intercepted it.

The official said that although he could not reveal its sources, Israel had clear evidence that the shipment was headed for Gaza and that the weapons, with ranges that could hit civilian populations in Jerusalem, Tel Aviv and Haifa, would have been a game-changer in the region.

“What we see here is a demonstration of how the Iranian regime is a major exporter of terror, especially to the Middle East, but also all over the globe,” Israeli Defense Minister Moshe Yaalon said. “Behind the charm offensive and the smiling, the Iranian regime is arming and financing terror factions.”