US Secretary of State John Kerry at a summit in Rome on Friday. On Sunday, he warned that Israel’s settlements on the West Bank are an obstacle to peace. (Vincenzo Pinto/AFP/Getty Images)

Secretary of State John F. Kerry said Sunday that Israel is “heading to a place of danger” because settlement growth is eroding chances for a two-state solution and peace with the Palestinians.

Using unusually blunt language at the Saban Forum, an annual symposium on Israel at the Brookings Institution, Kerry said he had been “pushing uphill” with the Israeli government because a majority of the ruling coalition does not support a two-state solution.

“There’s a basic choice that has to be made,” Kerry said, noting that since the Oslo agreement of 1993 the Jewish settler population in the West Bank has mushroomed from 110,000 to almost 400,000. “That is: Are there going to be continued settlements, is there going to be continued implementation of the settlement policy, or is there going to be a separation and the creation of two states?”

The Israelis have been fearful that President Obama in the waning days of his term will lay out binding parameters for two states — one Israeli, one Palestinian. The outline could be in the form of a United Nations resolution, a forceful option, or a detailed speech that could more easily be dismissed.

Prime Minister Benjamin Netanyahu’s coalition partners have failed to heed his admonition to not provoke Obama. Education Minister Naftali Bennett, for example, has declared that “the era of the Palestinian state is over,” and has pushed to annex 60 percent of the West Bank where Jewish settlers live.

Kerry said the Obama administration has not yet decided whether to spell out its vision, though he said the United States will continue to veto U.N. resolutions that it deems as reflecting anti-Israel bias. Kerry acknowledged that the Palestinians bear a share of the blame, including inciting violence and schools that foster hatred against Israelis.

In his remarks, Kerry effectively laid out some details that he said already have been discussed regarding how a Palestinian state could exist while Israel’s security is ensured. He said Israelis, Jordanians, Egyptians, Americans and Palestinians could work together to maintain border security using drones and electronically monitored fences. In the event of an incident, Israeli troops stationed nearby could swoop in on helicopters within six minutes.

“Nobody’s talking about a turnover today,” he said. “It’s going to take years of work to evolve. It has to happen with the assurance you’re not turning the West Bank into Gaza.”

Speaking about an hour after Netanyahu addressed the group by satellite, Kerry rebutted the Israeli prime minister’s argument that the heart of the stalemate is not Jewish settlements but the Palestinian refusal to recognize the Jewish state.

“Leaders in Israel are fond of saying settlements are not the cause of the conflict,” he said. “I am not contending they are. But I cannot accept the notion they don’t affect the peace process, that they aren’t a barrier to peace.”

He suggested the obstacle was deliberate in concept: “If you have a whole bunch of people who are strategically locating outposts and settlements in an area so that there will not be a contiguous Palestinian state, they are doing it to be an obstacle to peace.”

Kerry noted that later this week the Israeli parliament will vote on whether to legalize dozen of outposts in the West Bank that are considered illegal because they have been built on private Palestinian land. The Israeli high court has ordered that the military must evacuate and demolish a Jewish settlement called Amona in the West Bank, home to about 40 families, for just that reason.

Netanyahu has called the legislation needlessly provocative, but Defense Minister Avigdor Lieberman said Friday that Israel should wait until President-elect Donald Trump takes office to decide the illegal outposts’ fate.

In his remarks to the Saban Forum, Netanyahu said peace could be advanced through a regional effort using “our new relationships in the Arab world” to get the Palestinians to the table.

But Kerry said that was wishful thinking.

“There will be no separate peace between Israel and the Arab world,” he said. “That is a hard reality.”

William Booth in Jerusalem contributed to this report.