Iran's revolutionary courts have resumed large-scale executions after a lull of several months. Close to 60 persons have been killed by court order since Wednesday.

While more than half of the executions in the past six days resulted from a crackdown on drug trafficking here, many of the condemned were charged with taking part in insurrections in rebellious provinces.

That part of the upsurge in executions appears to reflect the inability of the central authorities to put down disturbances by Arabs in the oil-rich province of Khuzestan, Kurds in Kurdistan and Turkish-speaking Azerbaijanis in the northwest provinces bordering the Soviet Union.

The revolutionary courts have ordered the executions of more than 800 persons since the start of trials in February 1979. Most took place last year, according to statistics kept by the Tehran Times, and English-language daily.

The current increase in executions started Wednesday with the crackdown on drug traffic ordered by Ayatollah Sadegh Khalkhali, the religious judge who gained attention last month when he publicly poked through the charred remains of eight U.S. servicemen killed in the abortive attempt to rescued the 53 American hostages.

On Thursday, two leaders of the outlawed Moslem People's Republican Party of Azerbaijan were executed in Tabriz after having been charged with taking part in demonstrations last December.

The demonstrations favored greater home rule for the Turkish-speaking provinces. The charges against the policital leaders included insulting Ayatollah Ruhollah Khomeini, leading the occupation of the local radio-TV station and arresting and torturing their opponents.

The same day, five persons accused of sabotaging the oil pipeline in Khuzestan were executed in the city of Abadan. On Friday, three other persons accused of the same crime were executed.

On Friday, six men charged with being founders of Forqan, a group accused of staging the assassinations of at least six high-level officials of the Iranian revolution, went before a firing squad here.

Two Kurds were executed on Saturday in Kurdistan's capital of Sanandaj on charges of taking part in a rebellion there aimed at gaining autonomy for Iran's 4 million Kurds.

Drug traffickers, though, made up the largest number of those executed during the past six days. The initial killings Wednesday of 20 persons convicted of drug violations comprised the biggest mass execution since August according to the Tehran Times' figures.

Khalkhali, who is reputed to have order 300 executions himself, including the shooting of 70 Kurds last summer, took over the war on drugs last week.

As many as 2 million of the 35 million Iranians are believed to be heroin or opium addicts. Cultivation of poppies is believed to have increased vastly since the overthrow of the shah in February 1979.

Iran is part of the world's largest drug-producing area -- the turbulent triangle of Iran, Afghanistan and Pakistan which has replaced the Golden Triangle of Southeast Asia as the major source of hard drugs for Western Europe and the United States.

Meanwhile, a three-member delegation of European socialists -- led by Austrian Chancellor Bruno Kreisky, the first head of government to visit here since the revolution -- left tonight after a day of talks with a Iranian political and governmental leaders.

Although the three men said they were on a fact-finding mission for the Socialist International, a group made up of socialist parties from 42 nations, there was widespread speculation here that they sought some way to arrange for the freedom of the Americans held hostage since Nov. 4. Kreisky was accompanied by Olof Palme, former prime minister of Sweden, and Felipe Gonzalez, leader of the Spanish Socialist Workers' Party.

The Associated Press added:

The United States, apparently hopeful of Soviet cooperation, said it might request a special session of the U.N. Security Council if Iran ignores the World Court order Saturday to release the 53 American hostages. i

The Soviet Union vetoed a Security Council resolution to impose sanctions against Iran in January.

U.S. Deputy Secretary of State Warren Christopher told reporters in Geneva, Switzerland, that the World Court's unanimous ruling has "dramatically changed" the hostage situation even though a top Iranian official called the decision "meaningless."

Christopher noted that the Soviet and Polish judges voted with the other 13 members of the international panel to order Iran to free the captives, and he suggested that might indicate a shift in Kremlin thinking. Such a shift, Christopher said, would enable the United States to try "previously unavailable remedies" to force the hostages' release.

Two "remedies" he mentioned were an order by the Security Council that the hostages be freed or the implementation of sanctions against Iran under the United Nations Charter.