UN Assembly under way amid rising world tensions

The General Assembly opens today amid rising international tensions reminiscent of the worst period of the Cold War. In a recent speech, Secretary-General Javier Perez de Cuellar spoke of ''great international turmoil,'' alluding to East-West strains caused by the fighting in Lebanon, the South Korean airliner disaster, the nuclear arms race, and numerous regional conflicts.

He said it was essential that the session be marked by ''direct contact at the highest possible level'' to ease the tensions. But Soviet Foreign Minister Andrei Gromyko has already dashed hopes of new Soviet-US talks here by canceling his annual visit because of landing restrictions imposed against his flight on a Soviet jet.