Ryan: A “full explanation of the facts from the administration” is necessary.

Trump shared intelligence with Russia from close U.S. ally and detailed Islamic State operations; National security adviser issues denial, says ‘I was in the room, it didn’t happen’.

President Donald Trump shared sensitive intelligence obtained from a close U.S. ally with Russia’s foreign minister and ambassador in a meeting last week, according to U.S. officials, potentially jeopardizing critical intelligence-sharing agreements in the fight against Islamic State.

Mr. Trump met with Russian Foreign Minister Sergei Lavrov and Russian Ambassador Sergei Kislyak in the Oval Office the day after firing Federal Bureau of Investigation Director James Comey.

During the meeting with the Russian officials, Mr. Trump mentioned details about Islamic State in a way that revealed enough information for the Russians to potentially compromise the source, according to the officials, who said the intelligence came from the U.S. ally.

According to one U.S. official, the information shared was highly sensitive and difficult to acquire and was considered extraordinarily valuable. The Wall Street Journal agreed not to identify the ally because another U.S. official said it could jeopardize the source.

The Washington Post reported Mr. Trump’s disclosure and said White House officials called the Central Intelligence Agency and National Security Agency to warn of Mr. Trump’s disclosure and its possible consequences.

The White House denied on Monday that Mr. Trump disclosed any sources and methods of U.S. intelligence services or those of U.S. allies.

“I was in the room. It didn’t happen,” National Security Adviser Lt. Gen. H.R. McMaster said in a statement outside the White House.

Gen. McMaster said in his statement that Mr. Trump didn’t divulge intelligence sources, methods or military operations, but he stopped short of denying that the president had shared any intelligence or other secrets with the Russians.

It was the latest in a string of controversies, all stemming from investigations into Mr. Trump’s associates and presidential campaign over ties to Russia. Mr. Trump last week fired Mr. Comey, who was heading up the investigation into the ties between Trump associates and Russia and testified about the probe.

“If it’s true, it’d be troubling,” said Sen. Lindsey Graham (R., S.C.).

“It’s so mind-boggling, I don’t even know what to say,” said Eric Edelman, a former undersecretary of defense during the George W. Bush administration. “I’m completely gobsmacked. It’s jeopardizing a human source. It’s the one thing you’re trained to never do.”

On Capitol Hill, the report of Mr. Trump’s possible disclosure of classified information to the Russia’s top diplomat and its U.S. envoy prompted a chorus of concern from Democrats and Republicans.

A spokesman for House Speaker Paul Ryan (R., Wis.) released a statement calling for a “full explanation of the facts from the administration.”

“We have no way to know what was said, but protecting our nation’s secrets is paramount,” said Mr. Ryan’s spokesman, Doug Andres.

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