WASHINGTON (AP) _ Indian Prime Minister Rajiv Gandhi said Friday that the poison gas leak that killed more than 2,000 people at Bhopal, India, last year showed that U.S. firms conduct themselves less responsibly abroad than at home.

Asked if that conclusion could be drawn from the disaster at Union Carbide's Bhopal plant, Gandhi told a National Press Club news conference: ''In one word, ' yes'.''

The prime minister said he was reluctant to comment on his government's damage suit against the U.S. owner of the Bhopal plant because it is still in court.

Asked if he had anything to say about the company, Gandhi replied, ''The way they have behaved after the incident, we feel, is not good enough. They have looked very much down on people who lost their lives, including breadwinners.''

He said the Indian government believes Union Carbide ''should have informed us'' about the kinds and quantities of chemicals it was using or had stored at Bhopal, ''so that we could have had adequate medical facilities available.''

The Indian government recently rejected an offer by Union Carbide to pay $5 million in compensation to the victims without admitting liability. India said a federal judge in New York, where multimillion-dollar damage suits against the victims are being consolidated, had imposed unreasonable requirements on reporting use of the money.

The judge directed Union Carbide to pay the money to the Red Cross in the interest of getting relief to those injured or sickened by the leak.