US secretary of state John Kerry has told a private meeting of international figures that Israel risks becoming "an apartheid state" if a two-state solution is not concluded in talks between the country's leaders and their Palestinian counterparts.
"A two-state solution will be clearly underscored as the only real alternative. Because a unitary state winds up either being an apartheid state with second class citizens - or it ends up being a state that destroys the capacity of Israel to be a Jewish state," said Kerry, in a recording of his speech to the Trilateral Commission obtained by US news site The Daily Beast.
In his remarks to Russian, US, European and Japanese officials, Kerry reiterated the importance of reaching a two-state solution in the region.
"Once you put that frame in your mind, that reality, which is the bottom line, you understand how imperative it is to get to the two-state solution, which both leaders, even yesterday, said they remain deeply committed to."
According to the 1990 Rome Statute, the crime of apartheid includes "inhumane acts... committed in the context of an institutionalised regime of systematic oppression and domination by one racial group over any other racial group or groups and committed with the intention of maintaining that regime".
The controversial remarks - the first time a US politician has connected apartheid to the state of Israel - have sparked outrage among leaders of the American-Jewish community after peace talks collapsed between Israeli Prime Minister Benjamin Netanyahu's Likud coalition and President Mahmoud Abbas' Palestinian Authority last week.
Former White House Press Secretary Ari Fleischer tweeted that Kerry's remarks were "disgusting" and that Obama "must repudiate Kerry" for his actions.
Netanyahu nixed the negotiations after Abbas signed a concilliatory deal with the Islamist Hamas group which controls the Gaza Strip and is considering a terrorist organisation by Israel and the United States.
Jen Psaki, the spokesperson for the US State Department, said: "Secretary Kerry, like Justice Minister Livni, and previous Israeli Prime Ministers Olmert and Barak, was reiterating why there's no such thing as a one state solution if you believe, as he does, in the principle of a Jewish State."
"[Kerry] was talking about the kind of future Israel wants and the kind of future both Israelis and Palestinians would want to envision.
"The only way to have two nations and two peoples living side by side in peace and security is through a two state solution. And without a two state solution, the level of prosperity and security the Israeli and Palestinian people deserve isn't possible," she added.
Kerry also suggested that a change in the leadership of either Israel or the Palestinians could make a breakthrough in the talks a reality.
He also condemned Israel's approval of 14,000 new settlements in the occupied West Bank since peace talks began in July last year.
The revelation of Kerry's remarks came on the eve of Holocaust memorial day, a commemoration of the six million Jews who died during the Second World War.