SQL & PL/SQL :: Character String Buffer Too Small?

I'm trying to create a table with a select statement. I want to populate this new table with the aggregated value from a VIEW. Following is the code used for creating the VIEW,

create or replace view FINAL_WEB_LOG
as
select SESSION_ID,
SESSION_DT,
C_IP,
CS_USER_AGENT,
tab_to_string(CAST(COLLECT(web_link) AS t_varchar2_tab)) WEBLINKS
from web_views_tab
group by C_IP, CS_USER_AGENT, SESSION_DT;

I want to create a table with WEBLINKS and SESSION_ID which is a sequence from another table.

CREATE TABLE FINAL_WEB
AS
SELECT weblinks
FROM final_web_log
UNION
SELECT session_id
FROM WEB_VIEWS_TAB;

This now gives me the following error,

SQL Error: ORA-06502: PL/SQL: numeric or value error: character string buffer too small

This has to do with the field, Weblinks, it does have longer values.