President Donald Trump responded Tuesday to the resignation of his embattled national security adviser by saying that “the real story” is who leaked information about him to the press.

The real story here is why are there so many illegal leaks coming out of Washington? Will these leaks be happening as I deal on N.Korea etc? — Donald J. Trump (@realDonaldTrump) February 14, 2017

Michael Flynn, a retired general, stepped down on Monday over allegations that he spoke to the Russian ambassador last year about the possibility of easing sanctions that then-President Barack Obama had placed on Russia. The conversation would have taken place before Trump took office, and it’s illegal for private citizens to engage in diplomatic talks.

Trump may have been referring in his tweet to reports of North Korea’s missile test, which he appears to have discussed in the middle of the public dining area of his Florida club. One club member posted photos of the meeting on Facebook. It’s unclear whether the president and Japanese Prime Minister Shinzo Abe, with whom he was dining when the news broke, were handling classified materials.

Earlier on Monday, The Washington Post reported that the Department of Justice had previously warned the White House about Flynn’s relationship to Russia.

Retired Lt. Gen. Joseph Keith Kellogg Jr. will serve as acting national security advisor until Trump appoints a replacement.