The Reagan administration yesterday rejected a petition from U.S. copper producers to impose either quotas or higher tariffs on copper imports.

The administration's decision turned down the restraints recommended by the International Trade Commission (ITC) and overruled the position of its own Secretary of the Interior, William P. Clark, who said some protection was needed for the embattled domestic copper mining industry.

The administration's action brought an immediate response from mining industry representatives, one of whom called the decision "a sad commentary on American trade policy."

A sub-cabinet Trade Policy Review Group last month overwhelmingly recommended that President Reagan reject an ITC finding of June 14th that imports of foreign copper were a substantial cause of injury to domestic producers.

The ITC had recommended that either quotas or higher tariffs be used as remedies. But that proposal also was rejected by the Cabinet review group.

Clark -- at odds with the White House -- stated his position in an Aug. 14 letter to G. Frank Joklik, president of Kennecott Corp., a Utah copper company.

Clark said his department favors "action by the government to provide relief" that would force world copper prices "to rise to a more realistic level, while having the least objectionable effect upon domestic fabricators." Electrical and automotive companies are among the big copper users.

But U.S. Trade Representative William E. Brock said yesterday that imposing restraints on copper would raise copper prices and would wipe out many domestic fabricator jobs.

"The president determined that import restrictions on copper are not in the overall national economic interest," Brock told reporters at a hastily arranged news conference held at the end of the business day.

"Import restrictions would seriously disadvantage the copper fabricating industry. Higher copper prices would burden manufacturers of a variety of products from radiators to transformers, to telephone wires," Brock said.

That burden would "throw many people out of work" in the U.S. copper fabricator businesses, Brock said.

The National Electrical Manufacturers Association contends that as many as 10,000 fabricator jobs could be lost if import quotas were imposed on copper. Domestic copper fabricators exported $712 million worth of products overseas last year. NEMA says those shipments represented 17,800 U.S. jobs, many of which could be lost if restrictions raised the price of exported copper products.

The petition for restraints was brought by 11 major U.S. copper mining companies operating mainly in Arizona, Montana, New Mexico and Utah. The companies employ about 20,000 people.

The copper fabricating industries mostly are located in the Midwest and Northeast and employ about 150,000 people.

The administration's "feeling that far more jobs would be lost than gained" by imposing restraints was "the largest single factor" in its decision against the copper mining companies, Brock said.

"We are extremely disappointed and shocked by the president's decision. It's a sad commentary on American trade policy that the one case unanimously affirmed by the ITC was totally rejected by the administration," said Richard O. Cunningham, a counsel to the Coalition of Copper Industry Companies, which brought the complaint.

The domestic copper mining industry lost $414 million last year, and has laid off 15,000 workers since 1981. U.S. copper mines are operating at about 60 percent of capacity.

Cunningham suggested that the companies may attempt to seek legislative relief for their complaints.