World Notes DISARMAMENT

Just after the U.S. and the Soviet Union conducted major weapons tests last week, Mikhail Gorbachev announced a shift in the Kremlin's arms-control policy. The Soviet leader declared that Moscow was now ready to conclude a separate agreement with the U.S. on medium-range missiles in Europe. Said he: "We are putting our proposals on the table of negotiations with the U.S. in Geneva."

Moscow had hinted at a similar separate deal last year. But ever since the October summit meeting between Gorbachev and Ronald Reagan in Iceland, the Kremlin has insisted that its proposals on reductions of strategic, medium- range and space and defensive weapons had to be considered as a package. In Iceland the two sides tentatively reached agreement on a "zero solution" -- removal of both superpowers' medium-range missiles -- but that was blocked when the Soviets demanded that all three topics be dealt with together.

Now, said Gorbachev, the Soviet Union is willing once again to focus on Europe-based medium-range missiles. The U.S. had always wanted to do this in order to avoid any compromises on Reagan's Strategic Defense Initiative, or Star Wars.

Earlier in the week the superpowers tested weapons from their existing arsenals in wastelands on opposite sides of the world. High above Canada's Northwest Territories, an American B-52 launched a cigar-shaped cruise missile over the frozen Beaufort Sea. After flying at 500 m.p.h. and occasionally skimming as low as several hundred feet, the weapon touched down smoothly in Alberta four hours after launch. It was the first successful cruise test in a year.

The Soviet Union last week conducted its first nuclear experiment in 18 months, after saying repeatedly that it would soon resume nuclear testing because the U.S. was doing the same. The news agency TASS announced that scientists had detonated a 20-kiloton bomb in Kazakhstan, near the Chinese border.