Assign user to user groups via GRC 10.0

Hello, gurus,

We currently running GRC 10.

I wondering if it is possible to assign user to user groups via GRC, using standard functionality?

Via tcode SUGR i can assign user to group, and in su01 i will see this assignment in GROUP TAB.

We need to maintain this assignment via CUP.

I will be glad for any help or advice that you can give me.

With best regards, Ivan.