Fresh support, tough agenda greet UN Assembly. Secretary-General sees new relevancy for UN as a force for peace

As the United Nation's 42nd General Assembly session opens today, the organization is enjoying a modest comeback. In his annual report to the Assembly, UN General-Secretary Javier P'erez de Cu'ellar referred to ``a perceptible rallying'' to the UN in recent months. He added: ``It is as if the sails of a small boat in which all the people on the earth are gathered had caught again - in the midst of a perilous sea - a light but favorable wind.''

A test of this rallying, compared with its years of perceived decline as a relevant force for peace, will come between now and the Assembly's adjournment in December. The session's agenda includes 147 items, many of them longstanding and some seemingly intractable.

However, observers say, there are at least incipient signs of what Mr. P'erez de Cu'ellar called ``a new chance for peace'' via the good offices of the United Nations. Among such developments:

The Secretary-General's invitation to meet with leaders in Tehran and Baghdad in the past three days. The meetings were a follow-up to a unanimously adopted Security Council resolution mandating a peacemaking role for him in efforts to end the seven-year Gulf war.

Washington's willingness to work through the Security Council for an arms embargo against either of the Gulf war belligerents if they refuse to abide by the Council's July 20 cease-fire resolution.

The proposals for a UN naval presence in the Gulf to avert a dangerous buildup of nations' fleets. The Secretary-General acknowledged a UN role for ``ensuring the safety of civilian ships and maintaining peace at sea.'' But he shied away from such a peacekeeping operation as complex and costly.

Minor progress at this month's UN-mediated talks on a Soviet troop withdrawal from Afghanistan following a peace pact. Afghanistan and Pakistan each chipped away at their long-frozen positions. Afghanistan dropped its pullout time frame from 18 to 16 months; Pakistan modified its demand for a 7-month period to 8 months.

An invitation to P'erez de Cu'ellar by the five Central American signatories of the Aug. 7 Guatemala peace plan to serve on the International Committee for Verification and Follow-up created under the accord. The Secretary-General welcomed the agreement as ``an important breakthrough.'' In an apparent allusion to the US-Nicaragua conflict, he pledged ``any additional assistance'' requested to lessen regional tensions.

Other developments this year show the the growing willingness of governments to use the UN as a go-between for defusing international conflicts. For example, North and South Korea have both turned to the UN with rival proposals for reducing tensions on the divided Korean peninsula.

Diplomats are banking on a thaw in US-Soviet relations under Soviet leader Mikhail Gobrachev's policy of glasnost (``openness'') to contribute most significantly to the UN's rejuvenation. The UN seems effective only on conflicts in which the superpowers' interests run parallel or at least do not collide.

The Assembly convenes under a cloud of near insolvency. P'erez de Cu'ellar warns that even with the reforms and economies mandated by the last Assembly, there is no assurance that the organization will be able to meets its payroll and other operating expenses for the rest of the year. The major contributor, the United States, alone owes over $360 million in budgetary assessments. Congress must still authorize the entire amount.