Should an Editor's Expression of Interest go in a Query Letter to an Agent?

[KK123]

If you have received an expression of interest from an editor at a publishing house for your manuscript but they cannot accept it until after you have received agent representation, should this Editor EOI be mentioned in a query letter to an agent (i.e. something along the lines of letting the Agent know that there is an editor out there who is interested? OR, would it be better not to mention it in the Query Letter, but rather save it as something to talk about once the Agent has asked for a phone call, or has offered representation?)

Let me know what your thoughts are on this!!

[Tabris]

If you're at the point where the editor is saying, "You need to be agented before we can move forward," then yes, I would put that in the query letter. (But maybe just ask the editor if you can negotiate with a literary attorney rather than using an agent.)

If you just met the editor at a conference and they requested the manuscript, and it's currently sitting in your slush pile, save that for the phone call.