Cost element change

Hi

we have a need to move a cost element from one cost element group to an another cost element group but under one top node in the below example i would like to move cost element 1 from CE group 1 to CE group 2. Is there any way to do so.

top node A

CE group 1

cost element 1

cost element 2

CE group 2

cost element 3

cost element 4

Thank you.