MOSCOW, Oct. 18--Lunik III has transmitted back to earth mankind's first pictures of the far side of the moon, the official Tass news agency announced yesterday. The official announcement said Lunik was "completing its first revolution around the earth" at 11:50 a.m. on its return trip from the moon.

"While rounding the moon, pictures were taken of its far side, which is invisible from the earth," Tass said. "The results of the scientific measurements and photographs are being processed."

Union Rejects New Proposals

WASHINGTON, Oct. 18--The steel industry yesterday proposed to arbitrate the issue of work rule changes--one of the main obstacles to a steel strike settlement. The union rejected the idea.

R. Conrad Cooper, chief industry negotiator, made the proposal at a hearing before President Eisenhower's fact-finding board in the 96-day-old strike.

He offered to submit company demands for more leeway in making local plant manpower changes in the interests of efficiency to a three-man arbitration board for a binding decision in 60 days.

Macmillan, Ike Disagree

WASHINGTON, Oct. 18--Although diplomats are reluctant to talk about it, British Prime Minister Harold Macmillan and President Eisenhower are falling out of step again on their march to a summit meeting with Soviet Premier Nikita Khrushchev.

A week-long round of top-level, top-secret exchanges among Western leaders reportedly showed yesterday that the basic difference of approach which was so evident earlier this year has become apparent again following Macmillan's Oct. 8 election victory.

Macmillan is reported to have been pressing hard to rush Eisenhower and De Gaulle into a conference with Khrushchev at the earliest possible date. His pressure has surprised American officials who had thought he would attach less urgency to a summit meeting once the British elections were over.