US President Donald Trump disclosed highly classified information to the Russian foreign minister about a planned Islamic State operation during their meeting last week, two US officials with knowledge of the situation said on Monday.
The intelligence shared at the meeting with Russian Foreign Minister Sergei Lavrov and Russian Ambassador Sergei Kislyak, was supplied by a US ally in the fight against the militant group, both officials said.
The White House said the allegations were not true.
"The story that came out tonight as reported is false," H.R. McMaster, Trump's national security adviser, told reporters at the White House, adding that the two men reviewed a range of common threats including to civil aviation.
"At no time were intelligence sources or methods discussed. The president did not disclose any military operations that were not already publicly known. ... I was in the room. It didn't happen," he said.
The White House also released a statement from Secretary of State Rex Tillerson, who said the meeting focussed on counterterrorism, and from deputy national security adviser Dina Powell, who said the Post story was false.
Reacting to the news, the Senate's No. 2 Democrat, Dick Durbin, called Trump's conduct "dangerous" and reckless." The Republican head of the Senate Foreign Relations Committee, Bob Corker, called the allegations "very, very troubling" if true.
One of the officials said the intelligence was classified Top Secret and also held in a secure “compartment” to which only a handful of intelligence officials have access.
After Trump disclosed the information, which one of the officials described as spontaneous, officials immediately called the CIA and the National Security Agency, both of which have agreements with a number of allied intelligence services, and informed them what had happened.
While the president has the authority to disclose even the most highly classified information at will, in this case he did so without consulting the ally that provided it, which threatens to jeopardise what they called a longstanding intelligence-sharing agreement, the US officials said.
In his conversations with the Russian officials, Trump appeared to be boasting about his knowledge of the looming threats, telling them he was briefed on "great intel every day," an official with knowledge of the exchange said, according to media reports.
US officials said they have long been concerned about disclosing highly classified intelligence to Trump.
One official, who requested anonymity to discuss dealing with the president, said last month: “He has no filter; it’s in one ear and out the mouth.”
One of the officials with knowledge of Trump's meeting with the Russian called the timing of the disclosure “particularly unfortunate,” as the president prepares for a White House meeting on Tuesday with Turkish President Tayyip Erdogan, an ally in the fight against Islamic State.
Trump's first foreign trip also begins later this week and includes a stop in Saudi Arabia, another Islamic State foe, and a May 25 NATO meeting in Brussels attended by other important US allies.
