Former Republican Sen. Phil Gramm harshly criticized the House Republican plan to border-adjust taxes in a Wall Street Journal op-ed published Thursday, providing critics of the proposal another highly influential ally.

Gramm, a Texan and former chairman of the Banking Committee, wrote that the House GOP proposals have “little basis in economic logic, hinder economic efficiency, violate the letter and the spirit of numerous trade agreements, subject the economy to excruciatingly painful adjustments, [and] expose America and the world to unacceptable economic risks.”