From Beirut to London, from Tunis to Rome, calls for a ceasefire ending Israel’s relentless bombing of Gaza were interspersed with the slogan: “From the river to the sea, Palestine will be free.”

To the crowds waving Palestinian flags, the chant reverberating across the globe expresses the desire for freedom from oppression across the historical land of Palestine. But for Israel and its backers, who label the phrase as pro-Hamas, it is a veiled call to violence that bears an anti-Semitic charge.

The United Kingdom’s Labour Party on Monday suspended Member of Parliament Andy McDonald for using the phrase “between the river and the sea” in a speech at a pro-Palestinian rally.

Earlier this month, Home Secretary Suella Braverman described pro-Palestinian demonstrations as “hate marches” and warned that the slogan should be interpreted as an indication of a violent desire for the elimination of Israel.

The Football Association in the UK has banned players from using the slogan on their private social media accounts.

Austrian police took a similar stance, banning a pro-Palestine protest on the basis of the chant and claiming that the slogan, originally formulated by the Palestine Liberation Organization (PLO), had been adopted by the armed group Hamas. German authorities declared the slogan forbidden and indictable and called on schools in the capital, Berlin, to ban the use of keffiyehs, the Palestinian scarf.

The slogan has previously drawn a sharp reaction in the West. In 2018, journalist Marc Lamont Hill was fired by CNN for calling for Palestinian freedom “from the river to the sea”.

Here is what you should know about the controversy:

What are the origins of the slogan?

Upon its creation by diaspora Palestinians in 1964 under the leadership of Yasser Arafat, the PLO called for the establishment of a single state that extend from the Jordan River to the Mediterranean Sea to encompass its historic territories.

The debate over partition predates the formation of the state of Israel in 1948. A plan put forward a year earlier by the United Nations to divide the territory into a Jewish state – occupying 62 percent of the former British mandate – and a separate Palestinian state was rejected by Arab leaders at the time.

More than 750,000 Palestinians were driven from their homes in what became known as the Nakba, or “catastrophe”.

The PLO leadership later accepted the prospect of a two-state solution, but the failure of the Oslo peace process in 1993 and of United States attempts to broker a final deal at Camp David in 2000 leading up to a second Intifada, the mass Palestinian uprising, have since resulted in a hardening of attitudes.

What does it mean?

To Palestinian and Israeli observers alike, different interpretations over the meaning of the slogan hang on the term “free”.

Nimer Sultany, a lecturer in law at the School of Oriental and African Studies (SOAS) in London, said the adjective expresses “the need for equality for all inhabitants of historic Palestine”.

“Those who support apartheid and Jewish supremacy will find the egalitarian chant objectionable,” Sultany, a Palestinian citizen of Israel, told Al Jazeera.

Freedom here refers to the fact that Palestinians have been denied the realisation of their right to self-determination since Britain granted the Jews the right to establish a national homeland in Palestine through the Balfour Declaration of 1917.

“This continues to be the crux of the problem: the ongoing denial of Palestinians to live in equality, freedom and dignity like everyone else,” Sultany said.

Tens of thousands of pro-Palestinian demonstrators marched through a rainy London on Saturday accompanied by several Jewish groups, which according to the SOAS lecturer was a sign that the slogan could not be interpreted to be anti-Semitic.

“It’s important to remember this chant is in English and it doesn’t rhyme in Arabic, it is used in demonstrations in Western countries,” he said. “The controversy has been fabricated to prevent solidarity in the West with the Palestinians.”

Pro-Israel observers, however, argue the slogan has a chilling effect. “To Jewish Israelis what this phrase says is that between the Jordan River and the Mediterranean, there will be one entity, it will be called Palestine – there will be no Jewish state – and the status of Jews in whatever entity arises will be very unclear,” Yehudah Mirsky, a Jerusalem-based rabbi and professor of Near Eastern and Judaic Studies at Brandeis University.

“It sounds much more like a threat than a promise of liberation. It doesn’t betoken a future in which Jews can have full lives and be themselves,” he said, adding that the slogan made it more difficult for left-wing Israelis to advocate for dialogue.

Mirsky argued that those who chant the slogan are “supporters of Hamas”, while Sultany claimed that those waving the green flag of the armed movement were the exception at the thousands-strong protests.

The controversy on Monday reached as far as the British parliament, when the Labour Party removed McDonald from office for saying: “We will not rest until we have justice. Until all people, Israelis and Palestinians, between the river and the sea, can live in peaceful liberty.”

The party claimed the British MP had uttered “deeply offensive” comments relating to the Israel-Gaza war. McDonald rebuffed the accusations, saying his words were intended as “a heartfelt plea for an end to the killings” in the region, according to local media reports.

Sultany saw the dynamic at play as “an attempt by Zionists and pro-Israeli propagandists to collapse the distinction between the existence of Israel as a state and the ideological apparatus of Jewish supremacy”. Through this distorted lens, “a call for egalitarianism and for the dismantlement of the system of apartheid becomes an existential threat”.

Israel’s use of ‘from the river to the sea’

Benjamin Netanyahu’s Likud party, which describes itself as conservative and nationalist, has been a staunch promoter of the concept of “Eretz Israel”, or the Bible-given right of the Jewish people to the land of Israel.

According to the Jewish Virtual Library, the party’s original party manifesto in 1977 stated that “between the Sea and the Jordan there will only be Israeli sovereignty”. It also argued that the establishment of a Palestinian state “jeopardises the security of the Jewish population” and “endangers the existence of the state of Israel”.

Israel’s ambassador to the UK, Tzipi Hotovely, has been among the promoters of international recognition of the Jewish historic claim to lands from the river to the sea.

The expansion of settlements in the occupied West Bank and East Jerusalem by successive Israeli governments is seen as an attempt by Israel to control the land from the Jordan River to the Mediterranean Sea, denying Palestinians’ aspiration for an independent state.

Mirsky, of Brandeis University, said that while Israeli public figures were using the biblical concept to claim political authority over all disputed territories, the issue was “hotly debated” within modern Israel.

Rather than focus on what sows division, Mirsky said “efforts should instead be directed towards finding solutions”.

“Let’s sit down and can we come up with ideas that practically will make life better for Jews and Arabs?” he said, including a new slogan that bridges the current divide.

“As outlandish as this sounds, I do think that at the end of this war, there will be a new opportunity to talk about creating a better future.”