Analytical verification

We have performed the analytical verification of Drug Substance as per USP. Analytical method is similar to Ph. Eur. & IP of the subjected drug substance.
Does the subject drug substance require independent verification as per EP and IP?

Please specify the reason of performing Analytical method verification as per USP. Is it because the drug substance monograph (specification) and method of analysis are as per USP?
If not, then it is necessary to perform analytical method verification as per EP / IP method.
Please let us know what test are you referring to here.