ALGIERS -- Algeria promised action against a security lapse that resulted in the hijacking of a French jetliner and the murder of three hostages. But international concern was growing Thursday over how safe Algeria is.


A French tanker turned away from one port, French passenger transport links have been cut pending security improvements, and insurers in London were considering putting Algeria on a war risk list.


The hijacking that ended Monday night when French commandos stormed the plane in Marseilles and killed the four gunmen was the most dramatic incident in a nearly 3-year-old Moslem fundamentalist insurgency linked to the hijacking.


It was the year's third incident of sky piracy originating from Algiers' airport.


''There were lapses and failures in the exercise of responsibilities,'' government spokesman Ahmed Attaf acknowledged to Algerian reporters, the independent newspaper Liberte and other dailies reported.


Attaf would not elaborate on exactly what went wrong. ''We have to wait for the results of the investigation to take the necessary measures.''


Houari Boumedienne Airport limits access to people with tickets. Police check passengers with metal detectors and baggage is scanned and searched. Somewhere, Attaf indicated, the process broke down.


Four Moslem militants commandeered the Airbus A300 with 227 passengers and 12 crewmembers during boarding. Three passengers were killed and 64 were released before the plane flew to Marseilles, where two more were freed, according to final figures compiled by Air France.


French commandos stormed the plane Monday evening, killing the hijackers and freeing the remaining 170 people on board. Twenty-five people were injured, including 13 passengers who were slightly hurt. Officials said earlier that 173 were rescued.


France halted its air and maritime passenger traffic after the hijacking began and promised to tighten security.


Paris insisted merchant shipping was safe, but the crew aboard the gas tanker Tellier refused to dock at the port of Skida on Wednesday and turned back to France, French union officials said.


In London, the War Risks Rating Committee, a panel of insurers, was considering putting Algeria on a list of countries with war risks that could raise premiums for shipments to the country. The decision was to be made at a meeting early next year, officials said, according to the French newspaper Le Figaro.


Attaf insisted that Algeria ''was not pressured by France'' when it allowed the jetliner to fly to Marseilles on Monday as the hijackers were demanding.


''There were constant consultations between the two countries,'' he said.


French officials, however, said firmly after the killing of a French hostage Sunday night that they would hold Algeria responsible for the French on board. Algeria allowed the plane to take off about two hours later.


The latest hijacking was led by a member of the Armed Islamic Group, which has claimed responsibility for the deaths of many of the 75 foreigners slain since September 1993.


Over the past year, foreigners have left Algeria in droves at the request of companies and governments.