Hours after the United Nations imposed tough new sanctions on North Korea, vehicle traffic on the bridge linking the isolated country with the Chinese border city of Dandong was lighter than usual, but drivers reported no increase in cargo inspections.

A representative from a Dandong-based company that facilitates cross-border trade said local authorities had this week restricted how many vehicles could cross into North Korea each day, from 300-400 earlier to about 100, a sign that sanctions are having some early impact.

The sanctions, described by the United States as the harshest imposed by the U.N. against any country in two decades, are aimed at starving North Korea of funding for its nuclear weapons program.