WASHINGTON (AP) — The Obama administration is urging Southeast Asia’s regional bloc to do more to combat human trafficking after two of its member states were blacklisted for failing to act decisively against exploitation of migrant laborers.

A Democratic senator also questioned whether Malaysia, one of the countries downgraded in a State Department report last month, should be excluded from a U.S.-backed trans-Pacific trade pact currently under negotiation.

Longtime U.S. ally Thailand was also demoted to the lowest level in the annual U.S. rankings of governments’ anti-trafficking efforts, principally over abusive practices in the Thai seafood industry.

Scot Marciel, the top U.S. diplomat for Southeast Asia, told a congressional hearing Tuesday the Association of Southeast Asian Nations is slowly beginning to address human trafficking but “can and should do more.”