BUCHAREST, ROMANIA, JUNE 20 -- Ion Iliescu was sworn in today as Romania's first freely elected head of state in a half-century in a ceremony that the United States boycotted to protest his use of rampaging miners to intimidate the opposition last week.

In an inaugural address to the National Assembly, Iliescu for the first time disavowed excesses committed by the miners here last Thursday and Friday, saying, "We unequivocally dissociate ourselves from all actions that transcended the legal framework."

But Iliescu continued to defend his decision to bring the miners to Bucharest after police action to break up a seven-week demonstration blocking a downtown square led to antigovernment rioting. And he made no mention of the U.S. demand that he promise not to call in the miners again.

In his 40-minute speech, Iliescu reiterated Romania's commitment to democratic practice and reliance on Western ties as if to suggest that last week's violence should not be held against his government. He acknowledged that international reaction had been "mostly negative," but said he hoped foreign governments would eventually understand his government's actions.

Ambassadors from the 12 European Community nations were present at the ornate 19th-century Athenaeum Concert Hall for the occasion. But some of them made clear that their governments were maintaining last week's freeze on a major aid and cooperation agreement with Romania.

"There's no difference in policy between ourselves -- the European Community -- and the U.S.," British Ambassador Michael Atkinson told journalists. "There's just a difference of tactics."

Citing Iliescu's repeated promises to further democracy in cooperation with opposition politicians, the ambassador added, "We all in the Western democracies are looking for deeds to follow up these words. I am not optimistic."

Similar skepticism was voiced by opposition leaders Radu Campeanu of the National Liberal Party and Ion Ratiu of the National Peasant Party, whose homes and headquarters were sacked by the miners. They both rejected Iliescu's versions of the violence and applauded the U.S. boycott.

Iliescu, who had served as interim president since the overthrow of longtime Communist dictator Nicolae Ceausescu in December, won 85 percent of the votes to defeat Campeanu and Ratiu in the May 20 elections, in which his National Salvation Front captured two-thirds of the seats in both legislative houses. In taking office today, Iliescu named interim Prime Minister Petre Roman to continue heading the government.

In his inaugural address, Iliescu appeared to stop well short of Washington's demand that Romanian authorities "publicly pledge that vigilantes," as Ambassador Alan Green Jr. described the miners on Monday, "will not be encouraged or allowed."

Iliescu acknowledged that "there was overreaction in the public order restoration process," and that institutions, party headquarters and homes were broken into, and citizens unconnected with the earlier {violence} . . . were roughed up." But the president insisted that the miners arrived only after last Wednesday's disturbances turned into a "true rebellion, an organized coup d'etat aimed at discrediting the country's lawful democratically elected political leadership at home and abroad."

"There are many things that entitle us to speak of premeditated action, organized and coordinated according to a scenario for destabilization," Iliescu charged, without listing the specific examples that he and other officials had provided last week.

In thanking the departing miners last Friday "for all they had done," Iliescu had accused "extremist rightist elements" of collaborating in an attempted coup with "remnants" of Romania's notorious pre-World War II fascist Iron Guard. He also told the miners that "we know we can rely on you" to return to Bucharest if needed in the future.

In his speech today, Iliescu declared that "the accusations that the authorities allegedly harshly repressed a peaceful antigovernment demonstration and sought to suppress the opposition are not only unreasonable but also unfounded and untrue."

But such tough talk addressed to Romanians was balanced by reassurances to the West about democratic pluralism and a market economy.

"Romania's renewal," Iliescu said, "cannot be conceived otherwise than in ever closer connection with the traditional democracy" of the West. Democracy, he added, "is not only majority rule, but also the right of the minority to exist, to freely express its opinions and to have its legitimate interests protected."

Meanwhile, officials at the International Committee of the Red Cross said they had been unable to contact Romanians arrested last week.