WASHINGTON — House Democratic leader Nancy Pelosi is suggesting Congress may not pass the new trade agreement reached by the United States, Canada and Mexico if labor and environmental provisions are not strengthened.

Pelosi says "there are positive things in this proposed trade agreement," but it doesn't include "real enforcement of the labor and environmental protections." She met Thursday with the U.S. Trade Representative Robert Lighthizer.

The three presidents signed a revised North American trade pact on the sidelines of the G-20 summit last week. It will take effect when approved by the legislatures of all three nations.

President Donald Trump has said he plans to formally terminate the old pact, so Congress will have to choose between accepting the new pact or going without a trade accord.