The Reagan administration yesterday endorsed a congressional call for the Chun Doo Hwan government in South Korea to reopen the suspended political dialogue with the opposition and take steps toward democratic freedoms and civilian rule.

The administration's endorsement of a nonbinding "sense of Congress" resolution came as a separate group of lawmakers headed by Sen. Edward M. Kennedy (D-Mass.) introduced legislation requiring economic sanctions against South Korea until it takes major steps toward democratization.

Several lawmakers also expressed outrage at a report provided by the State Department that the U.S. Armed Forces television network in Korea had censored U.S.-originated news broadcasts involving South Korean politics on 17 occasions from February 1985 to August 1986.

The report, presented by Deputy Assistant Secretary of State William Clark to the House Foreign Affairs subcommittee on Asian and Pacific Affairs, said the items that were kept off the air in deference to a list of "host-country sensitivities" included stories about opposition leader Kim Dae Jung, torture, antigovernment protests and talks between South and North Korea.

A Defense Department spokesman said later, however, that no such reports -- which are rebroadcasts from U.S. commercial television networks -- have been kept off the U.S. television network in Korea since last July. A lengthy interview with Kim on ABC's "Nightline" Wednesday night was rebroadcast in full on the U.S. Armed Forces station, the spokesman said.

Lists of "host-country sensitivities" requiring special prebroadcast clearance are maintained for 11 of the 23 U.S. forces broadcast operations abroad, according to the Defense Department.

A seven-point list presented by Clark yesterday was outdated, according to Defense. The current list for Korea includes criticism of Chun or "implication" of any presidential wrongdoing; criticism of the South Korean constitution; suggestions that Korea is a U.S. "satellite," and AIDS reports that could harm Korea's hosting of international meetings, such as next year's planned Summer Olympics.

Administration officials said reports from Seoul suggested that demonstrations against the government of President Chun had reached a new peak but that the government still appears to be in control. Officials said Washington is continuing to counsel against declaring martial law or taking other harsh military measures and to ask the Chun regime to resume the dialogue with the opposition that Chun broke off on April 13.

Kennedy and three cosponsors of the economic sanctions legislation, which is opposed by the administration, condemned both recent developments in Korea and the U.S. response to date. Speaking of charges of torture and denials of human rights and the use of clubs, guns and tear gas in the current disorders, Sen. Barbara A. Mikulski (D-Md.) told reporters, "This is not why Americans fought at Pork Chop Hill. This is not why we went to defend the 38th Parallel."

Kennedy charged that the administration "tilts toward the regime" and "has shown its own contempt for the struggle for democracy" in Korea as it has in South Africa and Chile. His bill -- which would deny Korea U.S. trade preferences, government-guaranteed loans and U.S. support for loans in multilateral banks -- is meant to "fill the vacuum" left by U.S. inaction, he said.

Rep. Stephen J. Solarz (D-N.Y.), who led the drive to develop the nonbinding "sense of Congress" resolution, said its endorsement by the administration yesterday would send a unified message from two branches of U.S. government at "a moment of great crisis" in Korea. The resolution "regrets" Chun's April 13 decision to stop the dialogue on the process for selecting Chun's successor and calls for its resumption "as soon as possible."

The resolution -- approved by the Asian and Pacific Affairs subcommittee, which Solarz chairs -- also asks Chun to facilitate dialogue by taking "concrete and meaningful steps" including granting broader political and press freedoms, releasing political prisoners and "civilianizing" politics. Chun has selected a longtime associate, retired general Roh Tae Woo, as presidential candidate of the ruling party -- making him Chun's designated successor.