As site engineer,the resident engineer insist to some changing not belong to the approved data ,how can you deal with him?

I will do these changes after taking a memorandum from him

I agree with Mr. Mushriq and Waleed....

There should be proper documentation on the said changes.And discuss during project meeting so that all concerned are aware of the changes.

Thanks for invitation -

He can be dealt with in a friendly and professional and Back to top management to solve simple shapes !!!