UKRAINE'S continued reluctance to part with the nuclear weapons it inherited after the breakup of the Soviet Union is making the United States and its allies increasingly uneasy.
Ukrainian President Leonid Kravchuk appears to understand the West's concern about a leftover arsenal that, by itself, would make his nation the world's third largest nuclear power. The Ukraine parliament, however, has proven far more intransigent about living up to Mr. Kravchuk's promises to scrap the weapons through ratification of the START I treaty.
In a phone call earlier this week, President Clinton obtained a pledge from Kravchuk that he will try again, in March, to get parliamentary approval of START I. But an agreement is still a long way from assured.
``We always expected that the [parliamentary] ratification was going to be a difficult process,'' said State Department spokeswoman Christine Shelley on Nov. 30.
Through recent actions, the Ukraine legislature has essentially listed conditions that it wants met before it agrees to nuclear disarmament. They include substantial financial reimbursement for the weapons - not only for the strategic long-range warheads which remain, but for short-range tactical warheads that have already been returned to Moscow.
The parliament also wants extensive security guarantees from both the US and its arch-rival, Russia. The guarantees would include a promise to refrain from nuclear or conventional attack, and to refrain from using economic pressure to settle political disputes. Security guarantees
Ukraine has been circulating a draft treaty in Western capitals in an attempt to obtain these guarantees in a formal form. US officials, for their part, think Ukraine is asking for a type of security they can't guarantee - that its geopolitical life will be perfect.
Ukraine, which looks on itself as a two-year-old vulnerable fledgling of a nation, sees things somewhat differently. It feels it needs all the protection it can get, especially from Russia, where nationalist politicians have lately speculated openly about retaking Ukrainian territory.
``For Ukraine it is a matter of survival,'' says Valerie Kuchinsky, deputy chief of mission at Ukraine's embassy in Washington.
As things stand now, the Ukrainian parliament has voted only to gradually scrap 42 percent of the 1,700 ex-Soviet warheads still on its soil. In a move particularly disturbing to Western analysts, the legislature has also said it does not consider itself bound to Kravchuk's pledge to subscribe to the Nuclear Non-Proliferation Treaty and make Ukraine officially a nonnuclear state.
It is not clear that things will be different in March, when Kravchuk says he will try again. Parliamentary elections are scheduled for the interim, but the political trend in the country is conservative, notes Jack Mendelsohn, deputy director of the Arms Control Association.
For his part, Mr. Mendelsohn says it is more than likely that Ukraine's reluctance is part of ``a massive shakedown'' to extract all the aid and security it can from the West for a nuclear arsenal that is one of its few political or financial assets.
The problem from Ukraine's perspective is that the weapons may be a wasting asset. First of all, they are dangerous and difficult to store. Secondly, Ukraine is unlikely to have the technical skills to maintain them in working condition.
``They are going to become more of a burden than an asset,'' Mendelsohn says. ``That point I suspect is approaching.''
Currently, Ukraine only has the strategic warheads in its physical possession. Their literal control, meaning the codes and electronic ``button'' necessary for their use, remain in Russian hands.
The mere hint that Ukraine might seek to contain and perhaps control the weapons by breaking the codes is roiling Moscow, however. On Tuesday, Russian Foreign Minister Andrei Kozyrev charged that Ukraine was risking a ``chain reaction'' across Europe that would restart the nuclear standoff of the cold war.
Certainly, if it sought nuclear status, Ukraine would make itself a pariah to the West, without promise of good relations or substantial aid. Ukraine may deter Russia
But according to one provocative analysis, the US should encourage Ukraine to retain its nuclear warheads. The US ``should tone down its warnings of the dangers of a nuclear Ukraine,'' writes University of Chicago political science professor John Mearsheimer in a recent issue of the journal Foreign Affairs.
Professor Mearsheimer bases his belief on one basic premise: that relations between Russia and Ukraine will eventually deteriorate, perhaps to dangerous levels. Neither security guarantees from the West nor conventional armies will make Ukraine feel secure under such circumstances, he says.
A Ukrainian nuclear deterrent, on the other hand, might stabilize its security relationship with its often-bullying northern neighbor. ``Ukrainian nuclear weapons would be an effective deterrent against a Russian conventional attack or nuclear blackmail,'' Mearsheimer writes.