Amend missing form 8606

I contributed to traditional IRA in 2023. However, I just filed my 2023 tax return without form 8606. Now I want to amend the return by adding form 8606. Can I just mail them the filled form 8606 with a statement explaining the situation, or form 8606 has to be accompanied by a form 1040X or something?

 

Thanks in advance!