The White House is concerned by what it said was "divisive rhetoric" used by Benjamin Netanyahu in the Israeli election campaign.
On Tuesday, Mr Netanyahu went back on his commitment to a Palestinian state and earlier promised to continue building settlements in the West Bank.
His comments heavily contradicted President Barack Obama's preferred approach to the Israeli-Palestinian conflict.
The US would communicate its concern directly to the Israelis, White House spokesman Josh Earnest told reporters.
He said Mr Obama would call Mr Netanyahu to congratulate him on his Likud party's election win in the coming days.
The administration would also evaluate its approach on the Middle East peace process after the Israeli leader's statement that there would be no Palestinian state under his watch.
Mr Earnest told reporters Mr Obama did not think that the victory would have an impact on the nuclear talks with Iran.
US Secretary of State John Kerry has already called Mr Netanyahu to congratulate him following the victory.
British Prime Minister David Cameron also congratulated the Israeli leader on Twitter.
Mr Cameron wrote: “Congratulations to Netanyahu on election result. As one of Israel’s firmest friends, UK looks forward to working with new government.”
A spokesperson for Mr Cameron said: “In terms of the government’s approach to lasting peace in that region, it hasn’t changed and the PM set it out when he visited Israel 12 months or so ago.
“He wants to see peace, he wants to see a two-state solution and we are going to – as one of Israel’s firmest friends – continue to do what we can to support that goal.”
But the Foreign Secretary Philip Hammond said was he was concerned by the position adopted by Mr Netanyahu.
Speaking at Hendon United Synagogue on Tuesday, before the election results, he said both the Israelis and Palestinians had left the international community exasperated in the efforts to forge a two-state solution.
Mr Hammond said a lack of progress would lead to more European states taking unilateral steps to recognise a Palestinian state.
Hannah Weisfeld, founder of the Yachad group in Britain, also criticised Mr Netanyahu’s comments.
She said: “When the Prime Minister of Israel makes it clear that he will never allow two-states for two-peoples, and runs a re-election campaign which drives wedges between communities, those of us whose commitment to Israel is steeped in a commitment to democratic values are distanced from Israel.”
Laura Marks, Board of Deputies senior vice-president, said: “It's hard, from here, to see that there is a better long-term solution than two autonomous states, living in harmony, where young people on both sides grow up in a climate of mutual trust.
“Recent events, and the election, need time to settle, and our hopes remain committed for a peaceful way forward.”
