Applicability of esi for works contract

Hi Team,

We had engaged a vendor who work in our premises for cafeteria renovation and issued purchase order to execute this work.

Its involved supply and labor as well. I noticed that this vendor doesn’t have the ESI registration.

Do I need to deduct ESI at 6.5% on labour charges. As a principle employer ?

if yes, could you please suggest how to proceed on this.

Regards

Mahesh