WASHINGTON - Secretary of State John Kerry was denounced by supporters of both Israel and the Palestinians on Monday for reportedly saying that Israel could become an "apartheid" nation if it does not reach a peace deal to create a separate Palestinian state.

Supporters of Israel in Congress and pro-Israel groups said Kerry's comment Friday was offensive because it compared Israel's treatment of ­Palestinians to the former South African regime's systematic segregation and oppression of black Africans.

Some Palestinian advocates, meanwhile, complained that Kerry's comment ignored that Palestinians already have second-class status in the country.

Kerry's comments came at a closed meeting of the Trilateral Commission, a private group seeking solutions to global problems. It was first reported Sunday by the Daily Beast, which said it had obtained a recording of the comment.

Jen Psaki, a State Department spokeswoman, didn't deny that Kerry made the comment. But she said his words on the dangers of a stalemate reflect his concerns about what could happen to Israel in the absence of a deal, rather than his views about its current ­condition.

The secretary "does not believe and did not state publicly or privately that Israel is an apartheid state, and there's an important difference there," she said. "Israel is obviously a vibrant democracy with equal rights for all its citizens."

Cantor demands apology

House Majority Leader Eric Cantor, R-Va., demanded that Kerry apologize to Israel, saying that the use of the word apartheid "has routinely been dismissed as offensive and inaccurate, and Secretary Kerry's use of it makes peace even harder to achieve." He said Kerry and the administration have "been too quick to blame Israel for obstacles in the peace process."

The American Israel Public Affairs Committee, an influential lobby group, said the comments were "deeply troubling. Any suggestion that Israel is, or is at risk of becoming, an apartheid state is offensive and ­inappropriate."

A pro-Palestinian group, the Institute for Middle East Understanding, took exception to Kerry's comment, issuing a fact sheet to argue that Israel already has a two-tier legal system in the West Bank and discriminatory practices against Palestinians living in Israel.

Over the years some Israelis — including Israel's first prime minister, the late David Ben-Gurion — have warned that their nation could become an "apartheid state" if it retained control of the Palestinian territories. But President Obama is among those who have rejected the term. He said in a 2008 interview that the term is "emotionally loaded, historically inaccurate."