162. Telegram From the Department of State to the Embassy in the Soviet Union1

155109. Exdis—military addressees handle as Specat Exclusive. Following NATO 06260 sent Action SecState June 30, 1977 repeated to you. Quote. NATO 06260. Subject: Warnke Briefing on CTB Discussion.

Summary: ACDA Director Warnke briefed the NAC June 27 on the June 13–16 US-Soviet exploratory talks regarding comprehensive test ban, noting in particular differences on PNEs, verification, and duration. The text of this report has been approved by Mr. Warnke. Action [Page 378] requested: Suggest Department repeat to AmEmbassy Moscow, all NATO capitals, and appropriate military addressees. End summary.

1. Briefing on the US-Soviet exploratory discussions regarding a CTB, which took place in Washington June 13–16, Warnke said the atmosphere was cordial and positive. The talks were very preliminary, in anticipation of USUKUSSR negotiations but were wide-ranging, covered key issues, and identified five important problem areas:

A) While both sides agreed that a CTB could make a real contribution to controlling the nuclear arms race and to non-proliferation, the US referred to them as “comprehensive nuclear test ban” talks and the Soviets referred to them as talks on “a general and complete prohibition of nuclear weapons tests,” the term used in the draft treaty submitted by the Soviets to the CCD at Geneva.

B) While both agreed that the talks should be conducted in a manner that would elicit maximum support from other countries, the Soviets wished to work out substantially full text of a possible treaty in trilateral talks. The US on the other hand wanted to develop only the key elements in the trilateral talks and then to elaborate a treaty in multilateral negotiations at the CCD.

C) The Soviets maintained that peaceful nuclear explosions (PNEs) are important to the Soviet economy, that a ban on PNEs would be inconsistent with Article 5 of the NPT, and that technical means are available to insure that military benefits are not derived from PNEs. The US on the other hand believed that a CTB must prohibit PNEs, and that no valid claim could be made that nuclear parties to the NPT were practicing discrimination by not providing nuclear technology benefits if they themselves had concluded PNEs had no such benefits and would be foregone. Not to prohibit PNEs, in the US view, would encourage proliferation and serve as a pretext for other countries to emulate the example of India. The US believed that there is no technical way to prevent either side from deriving military benefits from PNEs.

D) Regarding duration, the US and USSR agree that nuclear tests could be suspended on a trilateral basis for a certain time. However, there are differences regarding the length of time before withdrawal provisions could be invoked. The US preferred a longer period than does the USSR.

E) On verification, the Soviets stressed national technical means, mentioned willingness to exchange seismic data, and also noted the possibility of a type of voluntary on-site inspection by challenge, whereby the challenged party could either agree to on-sites or take action as it sees fit to satisfy the challenge.

2. In summing up, Warnke noted that PNEs seemed to be the biggest problem, that questions of verification remained to be worked out, and that differences on duration did not appear to be insurmountable. Trilateral CTB discussions, including the UK, would begin on July 13 in Geneva.

3. Pauls (FRG) asked whether the US considered harmless or at least tolerable small-scale tests that could not be detected by seismic methods. He also asked about the relevance of Soviet interest in cra[Page 379]tering PNEs and about Soviet interest in standardizing and harmonizing the design of devices for PNEs to facilitate verification. Svart (Denmark) asked about the genuineness of Soviet interest in PNEs for the Soviet economy and possible differences among USSR officials in this area.

4. Warnke said a great deal of work still had to be done before the US could determine what would be satisfactory to verify a CTB. At the same time, verification had to be considered from the standpoint of both a suspecting country and a country that might be tempted to cheat. While the US was an open society, the Soviet Union had the problem of potential defectors and would have to be extremely cautious not to place itself in a position where there is even a small chance of its being found undeniably to be cheating on a CTB agreement. He said the US had mentioned the possibility of tamper-proof unmanned devices to improve seismic detection capabilities, and would be exploring such possibility further with the Soviets. As to the use of PNEs for cratering, Warnke said the US believes that such use would be greatly constrained by the Limited Test Ban Treaty, and this might gradually limit Soviet interest in retaining PNEs for cratering. The Soviets had expressed interest in standardizing PNEs and foregoing any improvements in devices used for PNEs, as well as in facilitating on-site inspection and outside participation in all stages of PNEs. Warnke acknowledged that there might be differences among Soviet officials regarding the utility of PNEs, but added that the head of the Soviet Delegation appeared to have a deep interest in PNEs. End text.



  1. Source: National Archives, RG 59, Central Foreign Policy File, D770237–0319. Secret; Exdis. Sent for information to all NATO capitals; the Secretary of Defense; the U.S. Commander in Chief, Europe; the U.S. Naval Military Representative to the Supreme Headquarters of the Allied Powers, Europe, in Belgium; the Commander-in-Chief, Atlantic Command, Norfolk; and the U.S. Liaison Office to the Supreme Allied Commander, Atlantic, Norfolk. Drafted by Eric Newsom (EUR/RPM); cleared by Homer Phelps (PM/DCA) and James Timbie (ACDA); and approved by James Thyden (S/S).