The White House offered shifting explanations for President Trump’s disclosure of highly classified information to senior Russian diplomats last week, a scattered defense that began with an early-morning Trump tweet that he had the “absolute right” to share “facts.”

Administration officials went from denouncing the Washington Post article as “false” to either confirming or declining to challenge nearly every key aspect of the account, which described how Trump’s sharing of sensitive details about a terrorist plot jeopardized access to a stream of intelligence from a critical U.S. ally.

“As President I wanted to share with Russia . . . which I have the absolute right to do, facts pertaining to terrorism and airline safety,” Trump said in two postings to his Twitter account, the first at 7 a.m. He then shifted the focus from his conduct to prod the FBI “to find the LEAKERS in the intelligence community.”

Trump also enlisted his national security adviser, H.R. McMaster, to help contain the fallout from the latest damaging revelations about the administration’s relationship with Russia. Trump revealed the classified intelligence in a White House meeting with Russia’s foreign minister and ambassador one day after firing FBI Director James B. Comey over frustration with the bureau’s investigation of any ties between Trump associates and Russian officials.

Speaking to reporters at the White House, McMaster refused to say whether Trump had shared classified information with the representatives from Moscow, falling back on a refrain that Trump’s disclosures were “wholly appropriate.”

(Bastien Inzaurralde,Jayne Orenstein,Dalton Bennett,Alice Li,Whitney Leaming/The Washington Post)

“What the president discussed with the foreign minister was wholly appropriate to that conversation and is consistent with the routine sharing of information between the president and any leaders with whom he’s engaged,” McMaster said. “It is wholly appropriate for the president to share whatever information he thinks is necessary to advance the security of the American people. That’s what he did.”

McMaster did not explain how sharing classified information with Russian officials advanced U.S. interests. The long-standing adversaries sometimes alert one another to security threats, but otherwise engage in little if any intelligence cooperation. Indeed, U.S. spy agencies earlier this year concluded that their Russian counterparts engaged in an unprecedented covert influence campaign to upend the 2016 presidential election.

Current and former U.S. officials said that Trump went well beyond outlining basic threat information in his meeting with Russian Foreign Minister Sergei Lavrov and Ambassador Sergey Kislyak.

Trump described steps the Islamic State was taking to pursue a plot involving the use of laptop computers on civilian aircraft, officials said. He discussed measures the United States has taken to suppress the threat, including military operations in Syria. Trump also identified the city in the Islamic State’s territory where the U.S. ally had been monitoring the plot through a valuable and ongoing stream of intelligence.

Trump “revealed more information to the Russian ambassador than we have shared with our own allies,” according to one current U.S. official.

Trump did not identify the particular method of intelligence gathering employed in the operation or the partner nation. But officials cited concern that Moscow emerged from the meeting with clues that Russian spy agencies could use to zero in on the U.S. ally’s sources and methods.

The Washington Post withheld details about the intelligence-sharing arrangement and plot at the request of White House officials, who cited concern over national security. By Tuesday, however, the New York Times and other news organizations identified the partner country as Israel.

(Bastien Inzaurralde,Monica Akhtar/The Washington Post)

Israel has in the past complained about the United States’ inability to safeguard secrets. In a statement, the Israeli ambassador to the United States, Ron Dermer, said that despite the disclosures, “Israel has full confidence in our intelligence sharing relationship with the United States and looks forward to deepening that relationship in the years ahead under President Trump.”

The disclosures about the Oval Office meeting came as Trump prepares for his first foreign trip — a multi-stop itinerary that will take him to Saudi Arabia, Israel, Bethlehem in the West Bank, and the Vatican, as well as Brussels for European Union and NATO meetings and back to Italy for a gathering of the leaders of the Group of Seven leading industrial democracies. White House officials had hoped the trip would distract from some of the political turmoil in Washington, but it is now likely to be dogged by close scrutiny of Trump’s performance in multiple foreign settings and how allies react to him.

On Capitol Hill, both Republican and Democratic lawmakers expressed concern and alarm about the president’s sensitive disclosures to the Russians.

“As an intelligence officer by training, I know firsthand the life and death implications of safeguarding classified information,” Rep. Mike Gallagher (R-Wis.), a freshman lawmaker and former Marine intelligence officer, tweeted Tuesday. “Our allies and partners must have the utmost confidence that sensitive information they share with us will not be disclosed,” he wrote.

Senate Majority Leader Mitch McConnell (R-Ky.) pleaded for “less drama” from the White House.

Democrats, who had been demanding that Trump turn over any tapes of his conversations with Comey, broadened their requests to include transcripts of his meeting with the Russians.

Senate Minority Leader Charles E. Schumer (D-N.Y.) said Trump should release the alleged transcript “if [he] has nothing to hide.”

“Until the administration fully explains the facts of this case, the American people will rightly doubt if their president can handle our nation’s most closely kept secrets,” Schumer said Tuesday on the Senate floor.

McMaster sought to play down the significance of Trump’s disclosures during a briefing at the White House. But when pressed on specifics, McMaster confirmed certain essential aspects of the story and refused to address others.

He retreated from his initial assertion Monday evening that the Post article was “false,” saying that his remark applied only to its “premise.”

He refused to answer whether Trump had revealed classified information, saying that “we don’t say what’s classified”; acknowledged that Trump had wandered off script during the meeting; and confirmed that Trump had mentioned the city where the U.S. intelligence partner saw the threat emerging.

At one point, McMaster said that the information Trump revealed “was nothing that you would not know from open-source reporting.” But that raised the question of why his own aides had felt it necessary to place calls to the leaders of the CIA and National Security Agency to alert them to what Trump had disclosed.

At first McMaster said that his subordinates may have done so “from an overabundance of precaution,” but he then said he couldn’t be sure because he had not spoken with the subordinate who had made the calls, Thomas P. Bossert, assistant to the president for homeland security and counterterrorism.

Finally, McMaster said that Trump “wasn’t even aware of where this information came from,” a comment intended to reinforce that the president couldn’t have revealed the source but left open the question of why Trump had been kept in the dark on that detail.

Later in the day, following a meeting with the Turkish president, Trump responded to a shouted question about his interaction with the Russians last week, casting a rosier picture of the potential partnership between the two nations than even many of his own advisers think is realistic.

“We had a very, very successful meeting with the foreign minister of Russia — our fight is against ISIS,” the president said, using an acronym for the Islamic State. “So we’re going to have a lot of great success over the next coming years and we want to get as many to help fight terrorism as possible, and that’s one of the beautiful things that’s happening with Turkey. The relationship that we have together, we’ll be unbeatable.”

William Booth, David Nakamura and Elise Viebeck contributed to this report.