The US government is refusing to add its name to a growing list of countries that support moves to ban weapons in outer space.
At a world summit on space activities in Vienna the United States is digging in its heels over plans to include in the resolutions of the meeting a reference to military applications.
James M. Beggs, the administrator of NASA and the head of the US delegation, says the issue of arms in outer space is ''too complex'' to be discussed at the two-week United Nations gathering that some 1,000 delegates from more than 100 nations are attending. Mr. Beggs says that the proper forum for this debate is the United Nations Committee on Disarmanent, which is meeting in Geneva.
But the American attitude is causing concern to other delegations which want the meeting to come out strongly against the arms race in outer space. Javier Perez de Cuellar, the secretary-general of the United Nations, set the tone at the opening session when he said that moves to put weapons in space were like ''approaching storm clouds.''
Without mentioning the US and USSR by name he said that efforts by countries in this direction would ''divert urgently needed resources from programs of social and economic development.''
According to observers at the conference, both the US and the USSR are working on laser and particle-beam weapons that could be sent into space within the next few years. And the Soviet Union has already tested in orbit an antisatellite craft that could destroy American military satellites, for communication or navigation for example. The US, by contrast, is believed to be working on its own version of such a device, which it could put into space by mid-1983.
Between them, the US and the USSR spend about $20 billion each year on the military applications of space.
At the Vienna conference, the Group of 77, (now over 100 third-world nations) , has followed the line of the United Nations secretary-general. It says it wants to outlaw the ''testing, stationing, and deployment'' of weapons in space.
Such a move would supplement the 1967 Outer Space Treaty of the United Nations that forbids countries to put beyond the earth's atmosphere weapons of mass destruction such as nuclear devices but stops short of a wholesale ban.
At a meeting of the conference Aug. 16, Gerald Helman, a State Department official who is a member of the US delegation, balked at supporting a relatively low-key paragraph on militarization that many countries wanted included in the final text of the conference. The statement, which the Soviet Union indicated it was ready to support, referred to militarization of space as ''a major concern . . . which represents a danger to international peace and security.''
The text went on: ''In order for the peaceful uses of space to develop in a cooperative, constructive, and unhindered manner, it is necessary to forestall and reverse this unfortunate trend.''
Helman said at the meeting that the wording of the text caused difficulties. Afterward, sources said that this was because the US is unhappy about language that mentions militarization but leaves unclear whether this refers to all military activities in space, surveillance satellites for instance, or just offensive weapons such as lasers.
Another interpretation is that the US is sticking on this point because it does not want to give away any negotiating ground at the UN Committee on Disarmanent.
However it is clear that the USSR, by agreeing to some mention of the dangers of military activities in space, is winning a propaganda victory among the nations of the third world. The USSR is also making some play of the fact that last year it introduced to the United Nations General Assembly a draft proposal on the banning of weapons in space. This proposal is on the agenda of the Geneva talks on disarmanent.
Of the other countries at the meeting, only Britain so far has taken a strong stand behind the United States, with more limited support from the Australian representatives.
At one point the delegation of Algeria suggested that the conference should isolate the US by agreeing to a declaration on arms that everyone except the Americans could support. This suggestion, however, was ruled out of order in a bid to reach a consensus.
The issue has now been put off until the last couple of days of the proceedings which end Aug. 21. Other delegations are sure to put more pressure on the United States to agree to mention the subject. France and Italy have already indicated they will support some wording on militarization and other West European countries are expected to follow suit.