The head of Egypt's Muslim Brotherhood has called on Arab forces to confront Israel and for the international community to pressure the "Zionist government to withdraw from the land of Palestine."

The comments by Brotherhood General Guide Mohammed Badie came in a written statement issued May 17 to commemorate Nakba Day, when Palestinians and other Arabs mourn Israel's creation in 1948.

The statement – the existence of which was revealed Wednesday by the Investigative Project on Terrorism blog – reminds Brotherhood followers of the movement's decades-long "sacrifices" in efforts to destroy the Jewish state.

"On this day, like every year, the Arab and Islamic nations remember the worst catastrophe ever to befall the peoples of the world," Badie wrote in the text, translated by The Jerusalem Post. "We demand the international community rectify the historic injustice [of 1948] and pressure the government of the Zionist entity to withdraw from the land of Palestine."

The statement portrays the Arab revolts of the last 18 months as part of an inexorable process to "liberate" land now in the State of Israel.

"We have toppled the most repressive regimes with purpose and determination," Badie wrote. "We have begun the era of liberation of all peoples, first of all the Palestinian people, [suffering from] the worst occupation known to man – the Zionist occupation."

Uriya Shavit, a lecturer in Tel Aviv University's Department for Arabic and Islamic Studies, said those acquainted with the Brotherhood's history will find the message unsurprising.

"The idea that the Brotherhood doesn't recognize the legitimacy of Israel, and the call to eradicate it at some point, is something the group has never denied. It's been in Brotherhood literature from its founding in 1928 until this very day," Shavit said.

"What they have tried to do, not just during the Arab Spring but before, is to try to reconcile the ideology of never recognizing Israel, or the 1979 Egypt- Israel peace treaty, with the understanding that if they're to be in power, they have to be realistic," he added. "That's why they offer statements like 'We realize we will have to recognize agreements signed by previous governments,' but then always add a 'but.'"

The Brotherhood took half of Egypt's parliamentary seats in elections earlier this year, with even harder-line Salafis taking another quarter. The Brothers' presidential candidate, Mohamed Mursi, barely edged former prime minister Ahmed Shafiq in firstround elections last month, and the two hopefuls will meet in a runoff ballot June 16-17.

Asked about Egypt's peace agreement with Israel, Mursi has variously called for its revision or for putting it to referendum. Aides to the candidate have said that if elected he would not meet with Israeli officials, though his assistants might.

Badie's Nakba Day message repeatedly cites passages from the Koran to explain political events. The Arab revolts showed popular will can topple "corrupt regimes which knelt at the feet of the Zionists," he wrote, adding the Koranic verse, "They are those with whom thou didst make a covenant but they break their covenant every time."

"The idea is there is no point in signing treaties with Jews – not Israelis, by the way, but Jews – because the Koran tells you just how unreliable they are," Shavit said. "This is rhetoric even Hamas has used less in the past year, because it's seen in the West as plain anti-Semitism, albeit in Islamic garb."

Dan Schueftan, director of the National Security Studies Center at the University of Haifa, said the question of Palestine has always been at the forefront of Brotherhood doctrine.

"This rhetoric has little to do with the Palestinians, and a lot to do with the fact that all this land is Muslim, and Israel is therefore inherently illegitimate," he said. "Egypt is moving from a bad situation to a much worse one. Naturally, Israel will suffer: when Egypt can't deal with its own problems, it will deflect them at us."

Nonetheless, he said, Israelis should watch developments in Egypt and across the region with a measure of both caution and confidence.

"I'm pessimistic and optimistic at the same time," he said. "Pessimistic about what's happening in the Arab world, but optimistic over Israel's ability to deal with it."