at someone's request
On being asked to do something, as in At my request they'll move us to another room, or I'm speaking at his request. [1300s] Also see by request.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.