WASHINGTON - The White House on Wednesday pointedly criticized Israeli Prime Minister Benjamin Netanyahu's successful reelection campaign and suggested his newly declared opposition to a Palestinian state could jeopardize America's unwavering support for Israel at the United Nations.

The blunt comments by Obama administration officials illustrated how the campaign tactics Netanyahu used to win an unexpectedly strong victory in Tuesday's election have further strained the historic ties between the United States and Israel. After six years of tension, relations between the two governments have frayed to a point not reached in decades.

Netanyahu made opposition to U.S. nuclear negotiations with Iran a centerpiece of his reelection effort. Then, in the closing days of the campaign, he said he would never agree to a sovereign Palestinian state, repudiating the concept of a two-state solution that has been a central element of U.S. policy under Presidents Obama and George W. Bush.

The Israeli leader had said in a major address in 2009 that his "vision of peace" included "two free peoples" living side by side in separate, independent states for Israelis and Palestinians. Many U.S. officials, as well as most Arabs, had questioned his sincerity, but Netanyahu's public reversal this week nonetheless marked a significant shift that administration officials rebuked Wednesday.

The United States would "reevaluate our approach" based on Netanyahu's "change in his position," White House press secretary Josh Earnest told reporters as the president flew to Cleveland to deliver a speech on economic policy.

State Department spokeswoman Jen Psaki raised the possibility that the reevaluation could include a shift in position at the United Nations. She avoided the usual U.S. language about vetoing Security Council resolutions that Israel opposes.

"The prime minister's recent statements call into question his commitment to a two-state solution," Psaki said. "We're not going to prejudge what we would do if there was a U.N. action."

Earnest also went out of his way to criticize one of Netanyahu's final campaign tactics: a videotaped warning to supporters that "Arab voters are streaming in droves" to the polls.

The United States was "deeply concerned about rhetoric that seeks to marginalize Arab-Israeli citizens," Earnest said, even though reporters had not asked him about the U.S. reaction. "It undermines the values and democratic ideals that have been important to our democracy and an important part of what binds the United States and Israel together."

A senior administration official, speaking on condition of anonymity, said that U.S. officials understood Netanyahu's "need to tack to the right" during his campaign. "We get that those are tactics," the official said.

But, the official added, referring to the prime minister by his nickname, "Bibi needs to understand that there are policy ramifications for the way he did this. You can't say all this" about rejecting the two-state policy "and then just say, 'I was just kidding.' "

Moreover, the official said, Netanyahu's comments about Arabs voting "made people recoil."

Obama in particular found the comments disturbing, a second senior official said.

Both on substance and rhetoric, the new Israeli government will be on a "collision course" with the United States as well as major European countries, said Itamar Rabinovich, who served as Israel's ambassador to Washington under Labor party governments during the mid-1990s.

Whether the two longtime allies can step back from such a collision - or even want to - will start to become apparent as Netanyahu negotiates to form a new governing coalition and U.S. officials decide how to respond to him.

Israel has often brought its influence to bear quietly, in private conversations with members of Congress and other top U.S. officials about security threats. Israeli officials could get to U.S. policymakers early, using assessments from their intelligence agencies to help steer American decisions.

Some of that trust and access will now be lost, former U.S. officials said.

Informal contacts have "been one of the most effective ways Israel has gotten what it wants," one former official said, speaking on condition of anonymity. "It won't be the same."

Already, in recent weeks, U.S. officials announced publicly that they were limiting how much information they would share with Israel about the nuclear negotiations with Iran. Netanyahu's government was using the data to denounce the American bargaining position in the talks, they said, accusing the Israelis of selective and misleading leaks.

At the same time, most of America's support for Israel has strong bipartisan backing, which is not likely to change.