Japanese phrase
こちらこそ。 ko chi ra ko so
Meaning
Thank you too.
When to use it
Shows that the speaker also has reason to be thankful. It is a warm response to thanks when both sides have helped or benefited.
Example dialogue
手伝ってくれてありがとう。 te tsuda tte ku re te a ri ga tō
Thanks for your help.
こちらこそ。 ko chi ra ko so
Thank you too.