Is it possible to use merge command when source file is parquet and destination file is delta? Or both files must delta files?

Currently, I'm using this code and I transform parquet into delta and it works. But I want to avoid of this tranformation.

Thanks

from delta.tables import *
 
deltaTablePeople = DeltaTable.forPath(spark, 'abfss://destination-delta')
deltaTablePeopleUpdates = DeltaTable.forPath(spark, 'abfss://source-parquet')
 
dfUpdates = deltaTablePeopleUpdates.toDF()
 
deltaTablePeople.alias('people') \
  .merge(
    dfUpdates.alias('updates'),
    'people.id = updates.id'
  ) \
  .whenMatchedUpdate(set =...