Hopes for peace in Israel are "slipping away", according to John Kerry.
The US Secretary of State said the idea of a one-state solution in the region was not viable, and affirmed the US's commitment to a two-state answer.
"We cannot, in good conscience, do nothing, and say nothing, when we see the hope of peace slipping away," Kerry said.
He added: "The truth is that trends on the ground - violence, terrorism, incitement, settlement expansion and the seemingly endless occupation - are destroying hopes for peace on both sides and increasingly cementing an irreversible one-state reality that most people do not actually want."
Downing Street said it was "not appropriate" for John Kerry to brand the Netanyahu administration as the "most right wing in history".
The Israeli prime minister said the country would stop funding for a number of UN bodies deemed as 'hostile' to Israel.