If the defendant in an action brought under section 112 would be entitled to bring against the plaintiff an action for infringement of the registered trade mark—
(a) the defendant may file in the court a counterclaim against the plaintiff for any relief to which the defendant would be entitled in the action for infringement; and
(b) the provisions of this Act applicable to actions for infringement apply in relation to the counterclaim as if it were an infringement action brought by the defendant against the plaintiff.