Donald Trump has admitted sharing intelligence on Islamic State with Russia, saying he had every right to do so.
The President returned fire in a pair of typically forthright tweets, after reports earlier today that he had shared highly classified intel with his Kremlin counterparts.
Trump said he shared "facts pertaining to terrorism and airline flight safety," adding he had "the absolute right" to disclose such information.
The Republican billionaire said he disclosed the information for "humanitarian reasons, plus I want Russia to greatly step up their fight against Isis and terrorism."
Russia earlier called the intel-sharing reports "fake news." Their response to Trump's tweets is unclear.
The disclosure is said to have occurred when the US president met Russian Foreign Minister Sergey Lavrov and the country's ambassador Sergey Kislyak last week in Washington.
The Washington Post broke the story, claiming Trump shared details of an unknown Isis plot, guarded by the US government and close allies of the country.
White House officials initially dismissed the reports, saying a broad discussion on counter terrorism was held in last week's talks, but no sources of intelligence or specific military methods were shared.
Senior figures in the Democratic party have called the potential leak "disturbing", with some calling for the President to fully brief Congress on the meeting.