dopping partition update index and UNDO generation

I have oracle 19c RAC on linux with pluggable database, on monthly basis maintenace activity occurs to drop old partitioin with almost 400GB

i would like to know if dropping the partition with update index

ALTER TABLE DROP PARTIOIN UPDATE INDEXES

would required use of UNDO tablspace as im noticing undo table space is getting bigger and bigger once this activity is being done, so wondering if its a coincidence or they are related

knowing that the drop statement is being done for almost 500GB from 20 Tables.