H.R.6420: To toll the congressional notification period for removing North Korea from the state sponsors of terrorism list.

Provides that the 45-day period referred to in specified Acts shall be tolled with respect to any rescission of the Secretary of State's determination that the government of North Korea has repeatedly provided support for acts of international terrorism until the President certifies to Congress that the government of North Korea has made a complete and verifiable declaration regarding: (1) the existence, number, and disposition of any assembled or partially assembled nuclear explosive devices; (2) attempts to enrich uranium or develop the capability to do so; and (3) nuclear assistance provided to any other countries.