Since an unique index will be created for PK automatically, can we specify which tablespace that index/PK should go to?

I tried the syntax

Alter table xx add constraint pk_xx primary key (col_name) tablespace index_tblsp;

And got error over there.

If I don't specify the tablespace when I create PK, then it will go to user's default tablespace. If I create PK inside table creation, then it will go to table's tablespace. Neither of them is what I wanted.

Any idea?

TIA...