SOFIA, Bulgaria (AP) _ Communist officials began talks today with members of the opposition, the Turkish minority and Slav majority on ethnic conflicts that erupted in a wave of nationwide protests last week.

The meeting at the National Assembly building, chaired by Parliament President Stanko Todorov, was called after four days of nationalist rallies against a decision by Communist leaders allowing ethnic Turks and Moslems to use their Moslem names and practice their religion without restrictions.

Ethnic conflicts have become more apparent in some parts of Eastern Europe, where hard-line Communist regimes were replaced by reformist governments last year.

The government news agency BTA reported that representatives from all official and opposition groups, as well as delegations from dozens of cities were taking part in the forum, which the agency termed unprecedented in Communist Bulgaria.

Todorov on Sunday night called for the weeklong ''social forum'' on ''several aspects of the national question.''

BTA did not identify who was taking part in the forum. It said the meeting today was to discuss how to organize the talks and that formal negotiations would begin Tuesday.

However, BTA said the participants unanimously approved an appeal to the people to call off all rallies and strikes to ensure a ''peaceful and business-like atmosphere'' at the talks.

At a rally Sunday, Bulgarian demonstrators threatened to start a general strike if their demands were not met that a referendum be held on the minority issue.

News media controlled by the 2-month-old leadership that replaced hard- liner Todor Zhivkov reported that local officials who are holdovers from the old regime appeared to be using the ethnic issue to try to stall reform.

But the media also reported a resurgence of Turkish nationalism in some areas, quoting witnesses as saying Turkish flags have been seen flying over public buildings in one southern city.

Premier Georgi Atanassov said the practice was illegal.

The demonstrators demand the repeal of a Dec. 29 order restoring rights to Bulgaria's 1.5 million ethnic Turks and Moslems.

That decision reversed the assimilation policy introduced by Zhivkov, who forced ethnic Turks to change their names to Bulgarian ones and barred them from speaking Turkish in public.

Nationalists among the Slav majority, who are mainly Orthodox Christian, fear the Turkish minority is growing too fast and poses a threat to the country of nearly 9 million. Slavs also are suspicious of the loyalties of the Bulgarian Turks and ethnic Bulgarian Moslems, known as Pomaks, since Bulgaria won independence in 1877 from the Ottoman Empire, which had ruled it for 500 years.

The government of Turkey, which lies on Bulgaria's southeastern border, and some Bulgarian Turks have blamed Zhivkov's hard-line Commmunist followers for instigating the unrest.

Bulgarian Foreign Minister Boiko Dimitrov is to meet his Turkish counterpart Mesut Yilmaz in Kuwait Tuesday for a second round of talks on the minority issue.

On Friday, thousands of Bulgarian workers walked off the job in at least five cities. Other demonstrations took place over the weekend.

''Bulgaria - a one-nationality country,'' read banners carried by some of the 10,000 ethnic Slavs who demonstrated in Sofia on Sunday outside Alexander Nevski Cathedral.

Standing in zero-degree weather, the protesters booed, hissed or chanted ''Resignation 3/8 Resignation 3/8'' as Atanassov and Interior Minister Atanas Semerdzhiev tried to address them.

In an apparent attempt to appease the protesters, Atanassov said Bulgarian would remain the official language. But both his and Semerdzhiev's speeches were drowned out.

''A hard time will befall the country whose people is divided,'' the official news agency BTA quoted Semerdzhiev as saying. He appealed to the crowd not to undermine ''the tendencies towards democracy in the country.''

BTA said residents from the southern town of Kardzhali, where almost half the 50,000 inhabitants are ethnic Turks, reported seeing Turkish flags on public buildings.

Atanassov, in a television address Sunday, said it was ''inadmissible to raise the flag of a foreign state at demonstrations and rallies in public and private places.''

He said the interior minister had been told to maintain public peace and ''neutralize any anti-constitutional and extremist acts under the framework of law.'' He did not elaborate.

A leader of the influential independent trade union Podkrepa, Nikolai Kolev, called for members to ''fight against all destructive forces.'' In a statement broadcast on state TV he said he thought nationalistic protests were being spurred by local officials.

While Petar Mladenov, who took over from Zhivkov as party leader Nov. 10, has moved quickly to put new people in the leadership more likely to support democratic reform, few changes have been made at the local level.

Some 320,000 ethnic Turks fled Zhivkov's persecution and emigrated to Turkey last summer, but at least 50,000 returned because of a lack of jobs and proper housing.

Elsewhere in Eastern Europe, a revolt by ethnic Hungarians against the Romanian government last month turned into a nationwide uprising that ousted dictator Nicolae Ceausescu.