PARIS, JUNE 17 -- The Soviet Union made a strong sales pitch for its commercial satellite launchings at the Paris Air Show today, putting heavy emphasis on Soviet reliability compared to setbacks in the European and U.S. space programs.

The presentation was a particularly visible step in the controversial Soviet campaign to sell commercial satellite launchings to foreign customers at a time when the Challenger space shuttle disaster and simultaneous delays in Europe's Ariane rocket program have caused bottlenecks in launchings of western satellites.

"It's part of the business," Valery Ignatov, head of the foreign licensing division of the Soviet Foreign Trade Ministry, said at a news conference. "I can tell you we are ready to carry out launches within one year of signing a contract."

U.S. officials have warned that sending American or European satellites to the Soviet Union for launching could give the Soviets a chance to steal advanced western technology.

"Everybody here, and also those not here, knows that if the Soviet Union were technologically backward, it would not have been able to create a manned orbiting space station . . . . It is only political reasons that make the U.S. administration react the way it does," said Oleg Firsiouk, deputy chairman of Glavkosmos, the Main Administration for Creation and Use of Space Technology for the National Economy and Scientific Research.

Firsiouk said the London-based International Maritime Satellite Organization (Inmarsat) approached Glavkosmos last year about launching one of its satellites. But the U.S. State Department discouraged Inmarsat officials from making such a deal and it fell through, he added. Both the Soviet Union and United States are among Inmarsat's 45 signatory states.

Stressing the point, Soviet officials making today's pitch handed out a list of six "security guarantees" they said would be accorded to any western company or agency that signed a contract for Soviet rockets to lift a communications or research satellite into space. These included a pledge that foreign technicians can escort any foreign equipment and control access while it is in the Soviet Union.

The Soviet Union, which has been selling launches for about two years, so far has won only one foreign commercial contract, from the Indian government, Ignatov said. That satellite, for observation and communication, will be launched before the end of the year, he predicted.

Firsiouk said Soviet scientists have launched 107 rockets into space since 1966 with only nine failed launchings. He and Ignatov said launching a communications statellite on a Soviet rocket would cost about $30 million as a base price, with other charges depending on the payload and type of orbit.

"The client should pay a reasonable rate," Ignatov said. "As a commercial organization, we can come up with a good price in every situation."

Competition in commercial satellite launching has become increasingly intense since the U.S. National Aeronautics and Space Administration launch program was derailed by the Challenger explosion 16 months ago.

Since then, the Reagan administration has taken NASA out of the commercial satellite-launching business. In the United States, three major rocket builders -- General Dynamics, Martin-Marietta and McDonnell-Douglas -- have announced plans for commercial launchings.

In addition to the European and Soviet programs, China also has begun to offer commercial launchings. Teresat Inc. of New York has contracted with China to launch a Westar VIS satellite in 1988 -- at a price reported at between $4 million and $8 million. Other contracts have been negotiated between China and Western Union, Canadian Telesat and a Swedish satellite company.