President Barack Obama said he takes Israeli prime minister Benjamin Netanyahu "at his word" for saying an independent Palestinian state will never co-exist with Israel as long as he is in office.
Mr Netanyahu has backpedalled since he stunned the US and the international community by announcing that dramatic policy reversal on the eve of his re-election on Tuesday.
But in his first public comments on the election outcome, Mr Obama suggested he does not believe the Israeli leader's softer position on the Palestinian state issue.
"We take him at his word when he said that it wouldn't happen during his prime ministership, and so that's why we've got to evaluate what other options are available to make sure that we don't see a chaotic situation in the region," Mr Obama told The Huffington Post.
Mr Obama, who placed a congratulatory telephone call to Mr Netanyahu on Thursday, said he indicated to the prime minister that the US remains committed to a two-state solution as the only way to keep Israel secure.
"And I indicated to him that given his statements prior to the election, it is going to be hard to find a path where people are seriously believing that negotiations are possible," Mr Obama said.
Tensions between the Obama administration and Mr Netanyahu escalated as the March 17 Israeli elections neared.
The White House was particularly annoyed when Mr Netanyahu accepted an invitation from Republican House Speaker John Boehner to address politicians earlier this month.
Mr Boehner had not consulted the administration before extending the invitation, which an infuriated White House said was a break from standard practice.
Mr Netanyahu sharply criticised a deal being negotiated among the US, Iran and other world powers over Iran's nuclear programme.
Mr Obama said US-Israeli military and security co-operation would remain unchanged, regardless of disagreements on policy.
"But we are going to continue to insist that, from our point of view, the status quo is unsustainable," he said.
"And that while taking into complete account Israel's security, we can't just in perpetuity maintain the status quo, expand settlements. That's not a recipe for stability in the region."
The president also criticised Mr Netanyahu for saying as the election neared that Arab voters were heading to the polls "in droves".
Mr Obama's spokesman Josh Earnest previously denounced the rhetoric as a "cynical election day tactic" and a "pretty transparent effort to marginalise Arab Israeli votes".
The president said: "We indicated that that kind of rhetoric was contrary to what is the best of Israel's traditions."
He added that Israeli democracy is premised on everyone being treated equally and fairly. "If that is lost, then I think that not only does it give ammunition to folks who don't believe in a Jewish state, but it also, I think, starts to erode the name of democracy in the country."
White House chief of staff Denis McDonough is scheduled to address J Street, an Israeli advocacy group that opposes Netanyahu, tomorrow.