U.S. National Security Adviser John Bolton adjusts his glasses during a meeting with Russian President Vladimir Putin at the Kremlin in Moscow, Russia October 23, 2018. REUTERS/Maxim Shemetov

MOSCOW (Reuters) - U.S. national security advisor John Bolton said on Tuesday a formal notification of the U.S. withdrawal from the Intermediate-Range Nuclear Forces treaty will be filed in due course.

Speaking at a news conference in Moscow after meeting Russian President Vladimir Putin, Bolton noted that when Washington withdrew from another arms control treaty in the past, it was a process that took several months.