Can't create table in procedure

I don't know PL/SQL well. Can you tell me why this doesn't work? Is there a problem creating tables in procedures?

CREATE OR REPLACE
PROCEDURE x AS
BEGIN
 CREATE TABLE XX
   AS SELECT * FROM transaction where transaction_id < 500 END; The error states it didn't expect CREATE Received on Wed Nov 29 2000 - 22:32:47 CET