US President Donald Trump has signed into law a measure placing sanctions on Iran, Russia and North Korea, a White House official said Wednesday.

The sanctions on Iran target its terrorist activities, human rights abuses and ballistic missile programs. North Korea is targeted for its nuclear weapons and ballistic missile programs as well as use of slave labor.

Trump said the new act is sending a clear message to each of Iran and North Korea that the American people would not tolerate their dangerous and destabilizing behavior and that the United States would continue work with all friends and allies to verify the stoppage of the malicious activities of those countries.

The Russia-related legislation, prompted by Russia’s alleged meddling in the 2016 US election as well as over Ukraine and Syria, includes a provision making it more difficult for the US president, who repeatedly quoted as calling for better relations with Russia, to ease the Russian sanctions without congress’ approval.