To find difference between two files on a whole

Hi,

The requirement is to compare two files that has single column of records each. Comparison is to happen on a whole and not line by line.

File1.txt

314589929
315611087
304924413
315989094
301171509
302984393
315609549
314593632

File2.txt

315611087
304924413
315989094
301171509

Now the output should be

314589929
302984393
315609549
314593632

I tried diff command, but it is checking the data line by line.
Please advise.

Based on the input given ..

$ fgrep -vf file2 file1

It works fine.
Thanks a lot!!!!!!!!!!!!!!!!1