In an interview with The Associated Press, he said Arabs will outnumber Jews in the Holy Land in the foreseeable future.
"If we look toward a one-state solution, which seems to be the trend — I hope not inexorable — it would be a catastrophe for Israel, because there would be only three options in that case," Carter said.
One would be to expel large numbers of Palestinians, which he said would amount to "ethnic cleansing."
The second would be to deprive the Palestinians of equal voting rights, which he said would amount to "apartheid."
The third would be to give the Palestinians equal voting rights, and therefore the majority, he said.
"And you would no longer have a Jewish state," Carter said. "The basic decisions would be made by the Palestinians, who would almost very likely vote in a bloc, whereas you would have some sharp divisions among the Israelis, because the Israelis always have different points of view."
Carter spoke to The Associated Press as his new book, "We Can Have Peace in the Holy Land," was released.
His wording on Israel's options was not new. His 2006 book, "Palestine: Peace Not Apartheid," provoked a hail of criticism, particularly from Jewish-Americans who felt it unfairly compared Israeli treatment of Arabs in the West Bank and Gaza to the legalized racial oppression that once existed in South Africa.
Carter still believes a two-state solution is the best option, with all of Israel's Arab neighbors recognizing its right to exist in peace, and Israel withdrawing from most of the land it captured in the 1967 Arab-Israeli War to create an independent Palestine.
The two major broadcasters maintain they must protect their journalistic impartiality.
When asked whether the appeal might lead to donations being co-opted by Gaza's ruling Hamas militants, Carter responded, "Not necessarily."
"You have to remember that about 70 percent of the total population of Gaza are refugees, and their extreme concerns are administered by the United Nations High Commissioner for Refugees," he said. "So the funds could be channeled through United Nations agencies, or through some other objective agencies, not through Hamas political leaders."