Prominent senators looking to restrict President Trump’s ability to enact tariffs are divided over which bipartisan legislation to support.

Sens. Pat Toomey, R-Pa., and Mark Warner, D-Va., introduced legislation in January that would limit Trump’s ability to unilaterally implement tariffs on national security grounds by requiring congressional approval first. Business lobbies such as the Chamber of Commerce, which oppose tariffs, have endorsed the Toomey-Warner approach.