SEOUL, JUNE 22 (MONDAY) -- Confronted by violent street protests that have raised the most serious challenge to his rule in its seven years, President Chun Doo Hwan today accepted recommendations from his party leadership that raised a high possibility of a meeting with the main opposition leader, according to state-run radio and local newspaper reports.

But the government unexpectedly postponed a statement it had planned to detail what concessions, if any, it would offer the opposition in order to defuse the unrest.

According to state-run radio, the chairman of the ruling Democratic Justice Party, Roh Tae Woo, recommended to Chun measures aimed at ending the crisis. Roh suggested wider contacts with opposition leaders, including Kim Young Sam, who heads the main opposition party, the radio said.

The reports said Chun had broadly accepted Roh's recommendations but did not specify that the president would meet Kim. Prospects for a meeting, which the opposition has demanded, were left unclear, because Kim has set two conditions: the release of all prisoners detained in the 12 days of protest, and the lifting of house arrest against another top dissident leader, Kim Dae Jung.

There was no indication that the government had agreed to meet those conditions, a step that would be a significant victory for its opponents. Ruling party sources, quoted in local newspapers Sunday, said a meeting of the party's parliamentary representatives had considered a lenient policy for detained protesters and the release of Kim Dae Jung.

A brief statement on state radio this morning said that the planned announcement on any possible political concessions had been put off for two or three days. It said Chun was seeking a greater range of views on the crisis, which has grown out of his refusal to negotiate on reforms to democratize South Korean politics, including direct presidential elections.

The postponement came shortly after the State Department's chief trouble shooter in the region said on the eve of a visit here that the United States believes that martial law or other use of military force "is not the proper approach" to stem growing political unrest here.

"We do not want to see the military involved," said Assistant Secretary of State Gaston J. Sigur Jr., speaking from Sydney on NBC-TV's "Meet the Press." "The proper approach to deal with the situation is to have the political leadership get together and reach an understanding of ways in which democracy can come more rapidly."

Sigur, who was in Australia with Secretary of State George P. Shultz, said he will try to pressure the South Korean government to hold open elections and resume negotiations with opposition leaders.

The White House sent a similar message to Seoul last week, but Sigur's trip was seen as an effort to underscore concern over what he said was an "obviously serious" situation. At the same time, western diplomats in Seoul said the United States is concerned that the visit may raise anxieties about the U.S. role and suggest analogies to visits by U.S. special envoys that preceded U.S. help in easing the Philippine ruler, Ferdinand Marcos, into exile.

"Some people are interpreting this visit as the first envoy," said one diplomatic source. He said Sigur had no "special message" and was not coming as a special envoy.

The streets of the capital were relatively quiet today. The narrow alleys in many parts of central Seoul that have been the battlegrounds between mostly student protesters and police were filled with shoppers, clearly enjoying the bright sunny weather and the noticeably reduced presence of police.

In one disturbance in the capital Sunday night, about 300 students who had gathered on the grounds of the Myongdong Cathedral went to confront riot police nearby, hurling firebombs. The police responded with tear gas, forcing the students back to the cathedral grounds.

Violent demonstrations continued Sunday in the provincial cities of Pusan, Kwangju and Taegu. In the southern port of Pusan, the country's second-largest city, several thousand students burned a police post, then marched peacefully for about three miles before police attacked them with rapid-fire volleys of tear gas, witnesses said.

State radio, quoting party officials, said Chun could help resolve the current political crisis by canceling his so-called "April 13 decision" to postpone until after next year's Summer Olympics a dialogue with the opposition aimed at amending the constitution to allow direct popular election of the president. The unpopular decision is commonly viewed as having helped generate support for the demonstrations.

Sigur said he would press for negotiations between the government and opposition over freedom of the press, government reform and freeing political prisoners.

"There are many steps that can be taken, the election law reform, the freedom of the press . . . local autonomy reform," he said. "I think what the Korean people would like to see would be an agreement among the government and the opposition as to just how to go about this. And that requires dialogue."

Sigur said he was uncertain whether he would meet with opposition leaders.

On the same program, Rep. Stephen J. Solarz (D-N.Y.), chairman of the House Foreign Affairs subcommittee on Asian and Pacific affairs, said it would be a "serious mistake" for Sigur not to meet with opposition leaders. "Not only would it make it impossible for him to reach an accurate assessment of the political crisis in that country, but I think it would send the wrong signal to the Korean people."

Richard Holbrooke, a former Carter administration official, told "Meet the Press" that to "minimize the possibility of a coup" the Pentagon and "every element of the American government" should let South Korean military leaders know "we discourage it." Sigur said he did not think there was a "serious" possibility of a military coup now. Washington Post staff writer Bill Peterson contributed to this report.