U.S. senators have introduced a bill that would impose new economic sanctions on North Korea, put it back on a U.S. terrorism blacklist and expand U.S. military cooperation with South Korea and Japan.

Republican Senator Sam Brownback of Kansas, the legislation's lead author, said Wednesday that Washington must take bold action to hold Pyongyang accountable for recent provocations and to end its reign of terror in North Korea.

The legislation directs the U.S. State Department to re-designate the North as a state sponsor of terrorism, which would reactivate sanctions lifted when Washington took Pyongyang off the blacklist in October.

The bill also requires the Treasury Department to ban U.S. banks from doing business with foreign banks which have engaged in financial transactions with Pyongyang or its senior officials.