PARIS, JULY 18 -- France and Iran maintained tight blockades around each other's embassies today, and Iran accused unnamed French diplomats in Tehran of spying, warning that they will have to face trial in an Islamic court.

The embassy sieges, accompanied by the new espionage accusations from Iranian Interior Minister Ali Akbar Mohtashemi, focused attention on the tense standoff between Paris and Tehran and yesterday's break in diplomatic relations.

Mohtashemi, in a speech relayed by the official Islamic Republic News Agency, said French diplomats inside the surrounded embassy offered assistance to antigovernment groups in Iran and therefore must be handed over to authorities for "Islamic justice."

Mohtashemi did not say how many or which French diplomats he was accusing. But his comments, monitored by news agencies, were taken as a sign of determination by Iranian authorities not to let French diplomats leave Tehran unless all Iranian officials are allowed to leave France.

Iranian authorities earlier had demanded only that a French consul in Tehran, Jean-Paul Torri, report to an Islamic court on charges of spying and drug trafficking. The French Foreign Ministry dismissed those charges as an attempt to create a false parallel with an Iranian official wanted here for questioning about links to terrorist bombings in Paris.

There was no comment from the ministry on Mohtashemi's broader accusations today. The tone of his comments, and their publication by the official Iranian news agency, suggested that the Iranian government may hold all those in the French Embassy as hostages to enforce its demand that Wahid Gordji, the Iranian official wanted here, be allowed to leave France for Iran.

The Foreign Ministry said more than 20 French officials are stationed at the Tehran embassy, including 11 with diplomatic status. In Paris, five diplomats are registered at the Iranian Embassy along with about 40 other officials, including Gordji.

French officials announced yesterday that diplomats from both of the surrounded embassies should be allowed to return to their respective countries within five days. This does not include Gordji, because he has only an official passport and thus is not covered by diplomatic immunity as defined in the Vienna Convention on diplomatic practice, they added.

An investigating judge, Gilles Boulouque, has demanded that Gordji report to his office for questioning on suspected contacts with terrorists who set off a wave of bombs last fall.

French police today served expulsion orders on four Iranian Embassy employes at their homes and ordered them to go into the embassy pending their departure from the country, Agence France-Presse reported.

Foreign Minister Jean-Bernard Raimond received families of French hostages in Lebanon at the ministry today amid heightened concern for the captives' safety.

Anonymous telephone callers told two western news agencies in Beirut yesterday that the break in relations with Iran meant two of the five French hostages in Lebanon would be executed. The calls' authenticity was uncertain, but the message intensified fears among the hostages' families and friends.

{In Beirut, the pro-Iranian group Hezbollah, believed by some in western intelligence circles to be behind the holding of some of the 24 foreign hostages in Lebanon, said France's decision to cut relations with Iran was an "atrocious mistake," United Press International reported. "Iran will not be alone in confronting this aggressive scheme and the universe will witness that all the Moslems will unite in defending Islam and awaiting the orders of {Ayatollah Ruhollah} Khomeini," Hezbollah said.}

Islamic Jihad, a Lebanese Islamic fundamentalist group with close ties to Iran, has recognized responsibility for the kidnaping of all but one of the French hostages.

Chirac maintained silence today on the break in diplomatic relations. In an indirect reference to the crisis, President Francois Mitterrand recalled that there are "clouds, storms and tempests" throughout the world in which France plays a role.

"France cannot be indifferent, especially when its interests and citizens are themselves caught up and worried by the tumult," he said in a speech.

The Foreign Ministry, meanwhile, said Italy has agreed to represent French interests in Tehran.