Donald Trump lashed out at "illegal leaks" Tuesday as the embattled president lost a key national security aide who stands accused of improper contact with the Russian government.

As his administration tried to draw a line under long-running suspicions of collusion with the Kremlin, Trump issued a Twitter missive.

"The real story here is why are there so many illegal leaks coming out of Washington?" Trump said.

"Will these leaks be happening as I deal on N.Korea etc?" he asked.