How to Merge Two .xls files side by side into a single .xls

Hi all,
please help me out in below requirement.
I have two .xls files say abc.xls and bbc.xls , i want to merge these two files into a single file ..say xyz.xls side by side
Ex:

abc.xls
Eno Ename
101 hello
102 hero
103 india

bbc.xls

Eno Ename
201 delhi
202 Hyd
203 bombay

My o/p file should be like this

xyz.xls
Eno Ename Eno Ename
101 hello 201 delhi
102 hero 202 Hyd
103 india 203 bombay

between these two one empty column should be there to distinguish..
please help me.. how do we do in unix..