White House economic adviser Kevin Hassett said on Sunday he was hopeful a dispute with Canada over accusations of the deadly fentanyl opioid entering the U.S. across its northern border could be resolved by the end of March.

His comments on ABC News’s “This Week” raise the possibility that tariffs due to be reimposed by U.S. President Donald Trump at the end of the month could be stayed further.

In reality, Canada is responsible for a minuscule proportion of drug smuggling into the United States and it wasn’t immediately clear what progress Hassett was referring to.

Democratic U.S. Senator Adam Schiff from California, who appeared after Hassett on ABC, called the adviser’s comments “incomprehensible.”