U.S. President Joe Biden said on Sunday he did not intend to intervene to prevent a port strike on the East Coast and Gulf of Mexico if dock workers failed to secure a new contract by an Oct. 1 deadline.

“It’s collective bargaining. I don’t believe in Taft-Hartley,” he told reporters.

Presidents can intervene in labor disputes that threaten national security or safety by imposing an 80-day cooling-off period under the federal Taft-Hartley Act.