Mention any one circumstance under which the Union Parliament may make laws on subjects in the State List.

The Union Parliament may make laws on subjects in the State List in the following cases:

1. During the Proclamation of an Emergency.
2. When the Rajya Sabha passes a resolution by a two-thirds majority that a subject in the State List has assumed national importance.
3. When two or more States desire that the Parliament should legislate on a subject given in the State List.