President Reagan and his top advisers have grown increasingly angry over Soviet delays in providing details to the world about the nuclear accident at Chernobyl, according to senior White House officials.

Reflecting this annoyance, Secretary of State George P. Shultz said at a press conference here yesterday that the United States already has "a much fuller picture than what the Soviets are presenting to us or, for that matter, to their own people."

At the same time, Shultz said the Soviets had firmly rejected offers of technical and medical help from the United States to cope with what Shultz called a disaster. The Soviets responded that they are "adequately equipped" to handle it, he said.

Reagan's first reaction to the nuclear accident, once it became known publicly on Monday, was to express concern and refrain from criticizing the Soviets. Late last night, before a dinner here with Indonesian President Suharto, Reagan answered, "no" when asked by reporters if he was annoyed at the Soviets.

But the White House officials said the president and other top advisers have privately become highly critical of the way Moscow is handling the accident.

"We took the high road initially," said a senior White House official who was part of the discussions. "We didn't see any purpose in zapping them." But when the Soviets refused to provide more details, the attitude quickly changed, he said.

"The Europeans are incensed, and we are, too," the official said.

Reagan and his advisers have grappled with the Soviet nuclear accident in the relative isolation of this tropical resort 11,400 miles from Washington. In between meetings with Southeast Asian foreign ministers and Suharto, Reagan was asking aides why the Soviets "didn't tell us sooner and tell us more," one official said.

Reagan and Shultz yesterday began to criticize the Soviets openly for delaying announcement of the accident for three days and for failing to disclose more information about it to the world once radiation was released into the atmosphere.

"Well, they're usually a little close-mouthed about these things and this is no exception," Reagan told reporters here as he opened a meeting yesterday with Suharto.

Presidential spokesman Larry Speakes said the Soviet authorities are keeping a "close hold" on information about the accident. He and Shultz repeatedly accused the Soviets of neglecting their responsibility to tell neighboring countries about the dangers posed by the release of radiation into the atmosphere.

"We're turning up the heat," said the White House official.

Speakes said the accident began Friday in one of the power block rooms at the Chernobyl reactor, but the United States did not learn of it until Monday from a report by the Soviet news agency Tass. Reagan was then flying here from Hawaii for the foreign ministers meeting. He leaves today for Tokyo and the seven-nation economic summit.

Shultz said information obtained by the United States, including satellite photographs, indicates that the Soviets have understated the loss of life resulting from the accident.

"Our own pictures give us information that suggests the casualty rates are higher than those that have been announced by the Soviet Union, so far by a good measure," he said.

"The fact is, from our own sources we know more than the Soviet Union has told us or other countries," Shultz said.

White House officials said Reagan's growing anger at Soviet delays in providing information about the accident was in part out of concern for the possible hazards of the spreading radiation. But the officials also said Reagan believed the Soviets had demonstrated what he has described as the failings of a closed society.

"It's a great contrast to the way information emerges on something of that kind, let's say, in the United States as compared with the Soviet Union," Shultz said, "because there would be a tremendous volume of information available if that accident had taken place" in the United States.

The Soviet rejection of two earlier U.S. offers to help with the accident came at a State Department meeting between Soviet charge d'affaires Oleg M. Sokolov and Deputy Assistant Secretary of State Mark Palmer, officials said.