Thank you for the message which reached me through Mr Kerr a few days ago. I have had a talk with Mr Kerr, and my impression is that our joint work will proceed in an atmosphere of complete mutual trust. I convey to you the Soviet Government's gratitude for the assurance that the British Government will treat any use of poison gas upon the U.S.S.R. by the Germans as if that weapon were directed against Great Britain and that the British Air Force will not hesitate to use the large store of gas bombs available in Britain for dropping on suitable targets in Germany.

According to our information poison gas may be launched against the U.S.S.R. not only by the Germans, but also by the Finns. I should like what you say in your message about retaliation with gas attack upon Germany to be extended to Finland in the event of the latter assaulting the U.S.S.R. with poison gas.

I think it highly advisable for the British Government to give in the near future a public warning that Britain would treat the use of poison gas against the U.S.S.R. by Germany or Finland as an attack on Britain herself and that she would retaliate by using gas against Germany. It goes without saying that, if the British Government so desires, the U.S.S.R. is prepared in its turn to issue a similar warning to Germany against a German gas attack upon Britain.

The Soviet Government holds that a British Government warning to Germany on the above lines should come not later than the end of April or early May.

The Soviet Government would be most grateful if the British Government could help the U.S.S.R. to obtain certain chemical means of defence it lacks, as well as means of chemical retaliation against eventual chemical attack upon the U.S.S.R. by Germany. If you have no objection I could send an authorised person to Britain shortly to take care of
the matter.

March 29, 1942