DHCP CHANGES/Scope changes.

I just got a request form my colleque from our intinational branch to change the ip scheme on the server. My domain controller host one of the DHCP server and i was wandering how to go about changing the scope to what is bent provided to me from UK. my adderss is ex: 10.80.4.4 which i’m running on dc1. The new adderss that is provided to us is as followed 10.261.12.4 the scheme has to be implimented for rest of the clients to obtain ip address of same scheme. Will this affect active directory and how is the best possible way to carry out this task. All suggestion are welcome. Thanks IN ADVANCE ALL