735 ILCS 5/12-666: Procedure for recognition of foreign-country judgment.

(a) If recognition of a foreign-country judgment is sought as an original matter, the issue of recognition shall be raised by filing an action seeking recognition of the foreign-country judgment.

(b) If recognition of a foreign-country judgment is sought in a pending action, the issue of recognition may be raised by counterclaim, cross-claim, or affirmative defense.