John Tower, the defense secretary-designate, told NATO strategists Sunday they should remain skeptical of Kremlin disarmament overtures and keep the West's nuclear options open.

The 16-nation Western alliance risks mortgaging its security if it fails to modernize its nuclear forces because of perceived improvements in the East-West relationship, he said.Under President Mikhail S. Gorbachev, the Soviet Union remains a powerful adversary with superior military capability, and the West must not lose sight of that imbalance in its euphoria over disarmament prospects, said Tower.

"If we fail to consider that capability, or if we fail to consider its relevance in terms of their intentions, then we do so at our peril," said the Texas Republican selected to head the Pentagon under President Bush.

In restating his support for extending the range of some European-based missiles, Tower joined other Americans who used the annual allied defense strategy session to try and woo West Europeans from their attraction to Gorbachev and the concept that the East bloc now poses less of a threat.

The weekend conference highlighted the gap between U.S. and European public opinion on defense needs. West Germans, especially, stake stronger hopes for disarmament on Gorbachev and are opposed to anything considered an expansion of nuclear weapons in Europe.

NATO's missile modification plan, adopted in 1983 and referred to as "modernization," is so sensitive in West Germany that the nation's defense minister carefully avoided giving it open support in a speech Saturday at the conference, which is dominated by hard-line supporters of modernization.

Tower met privately with the minister, Rupert Scholz, on Sunday but apparently failed to persuade him to show stronger support for NATO doctrine.

"We just illuminated some problems. We didn't come to any solutions," Tower told The Associated Press.

He declined to say whether he was able to get an assurance from the West German that Bonn would support modernization.

On Sunday, the conference focused on new and mounting threats to alliance unity posed by Gorbachev's "charm offensive," the broad public appeal generated by his array of proposals for disarmament and democratic reform.