Communicate with influence (5)
I believe the answer is:
reach
I believe this clue is a double definition.
'communicate with' is the first definition.
(I've seen this in another clue)
'influence' is the second definition.
(thesaurus)
(Other definitions for reach that I've seen before include "Come to - stretch of river" , "Attain - continuous extent of water" , "Sail with the wind abeam" , "bay" , "Put out the hand for a part of the river" .)