The death toll from the accident at the Chernobyl nuclear power plant has now reached 23, according to the American doctor who has been helping treat severely radiated patients.

Of those, 21 have died in Moscow after being exposed to severe radiation, said Dr. Robert Gale, a specialist who helped perform 19 transplants of bone marrow this month.

The deaths -- up from the 19 cited by a Soviet scientist here Monday and 21 by a Soviet cardiologist in Cologne, West Germany, yesterday -- leave 14 survivors among the group most severely affected by radiation.

Gale, who came here within six days of the accident and left two weeks later, a is back on a follow-up tour. He said he has been invited to go to Chernobyl by the Ministry of Health and will leave for the region on Sunday or Monday.

Gale gave a breakdown of injured and dead from the accident in an efort to clear up some recent confusion. Using figures given him by his Soviet colleagues, Gale said that between 250 and 300 people who required hospital care were selected during an initial check of 1,000 people after the accident.

Of that first group, 80 were determined to have received "important" doses of radiation, 35 of them "serious" amounts. All of the 80 were brought to Moscow, he said.

The 35 seriously affilicted patients were those treated by Gale, his two American colleagues and a doctor from Israel when they arrived on May 2. Of the 35, 21 have now died, Gale said. The other two deaths occurred at the time of the April 26 accident.

The other 45 patients received "important but lower" doses, Gale said. He has not treated them. Gale called correspondents to inform them of the latest numbers, saying he thought the totals had been stable throughout the last month.

"Frequently the problem is one group doesn't know what the other is doing," he said. "Nobody knows how many are in hospitals beyond their own."

Gale had been pressing Soviet authorities for an invitation to visit the Chernobyl region so he could make his own judgments about the safety of the environment and the quality of the health care.

Exiled Soviet physicist Andrei Sakharov has spoken about the Chernobyl nuclear incident with journalists and neighbors in the closed Soviet city of Gorki, according to a well-connected Soviet journalist, and his views are in harmony with the Kremlin's approach to the incident, the journalist asserted.

Sakharov was banished to Gorki in 1980 to bar him from contact with westerners. Yelena Bonner, his wife, is expected to end a six-month visit in the West next week and to rejoin Sakharov in exile. She has indicated that the two were only allowed to talk with local security officials guarding them.

Victor Louis, a Soviet journalist and often a source of information on Sakharov, said that the Nobel laureate talked to journalists from a Gorki newspapers and to neighbors who approached him about the Chernobyl affair.

"What he has been saying is pretty consistent with the policy here," Louis said.