My Dear Mr. Stalin:
This note will be presented to you by my friend Averell Harriman, whom I have asked to be head of our delegation to Moscow.
Mr. Harriman is well aware of the strategic importance of your front and will, I know, do everything that he can to bring the negotiations in Moscow to a successful conclusion.
Harry Hopkins has told me in great detail of his encouraging and satisfactory visits with you. I can't tell you how thrilled all of us are because of the gallant defense of the Soviet armies.
I am confident that ways will be found to provide the material and supplies necessary to fight Hitler on all fronts, including your own.
I want particularly to take this occasion to express my great confidence that your armies will ultimately prevail over Hitler and to assure you of our great determination to be of every possible material assistance.
Yours very sincerely,
Franklin D. Roosevelt, Letter Introducing W. Averell Harriman to Stalin. Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/210076