India's new opposition leader, Jagjivan Ram, Saturday sharply criticized the government being formed by Prime Minister Charan Singh and indicated he would work to defeat it in a parliamentary confidence vote next month.

Ram, who took over as head of the Janata Party following the downfall of former prime minister Morarji Desai's administration two weeks ago, charged that the new minority caretaker government has "no idea" what to do with power and is already falling apart.

In a nationwide broadcast, Ram said he doubted that a midterm general election would necessarily follow a parliamentary vote of no confidence for Charan Singh's government.He said he was sure that Indian President Sanjiva Reddy would simply call on the opposition Janata Party to form a new government.

Although the Janata Party, formerly led by Desai, lost power because of wholesale defections, it remains the largest in Parliament with more than 200 seats.

"I have no doubt in my mind that the Janta Party will be able to form a stable majority government," Ram said.

Singh's first days as minority prime minister have not been auspicious. Saturday six ministerial nominees from his coalition partner, the Congress Party, failed to turn up for the swearing in ceremony. This followed an internal rift in the party over their selection. Some Congress Party legislators objected to the fact that none of the selected ministers were Moslems or Harijans (Untouchables).

Ram himself is a member of the Untouchables, India's lowest caste.

After another meeting Sunday, the Congress parliamentary board decided to add one more name to the list of six nominees - that of Shafi Qureshi, a secretary general of the party, who is a Moslem. The board also recommended three other candidates to be ministers of state, including a woman and an Untouchable. Political observers considered it unlikely that this would seal the rift more than temporarily.

Support for Singh from other minority parties is also beginning to waver. The Congress Party branch of former prime minister Indira Gandhi has given notice that it no longer feels committed to support the new government.

Sources within Gandhi's party said future support may be conditional upon the dropping of charges against the former premier, her son Sanjay and her political colleagues for excesses committed during her 18-month state of emergency. Special courts recently have been established to hear the cases.

In his broadcast Sunday night, Ram - who feels that his own victory has merely been postponed - said that recent political developments had "betrayed" the faith of the people.

"The country is passing through traumatic times, but the response of the present government seems to be either platitudes or vague generalization," Ram said.

"We are told that the elimination of unemployment will be "accorded the highest priority," that the government will take "all necessary steps' to remove corruption, that "every possible means' will be used to promote small units in industry and agriculture and that the government will take "every possible step" to meet the problem of increasing prices," he said.

"Not a word about what all these possible steps are going to be," Ram said. "A group of people has been so busy using every possible means and taking every possible step to come into power that, now that they have achieved that objective, they have no idea what to do with it."

Ram said a crusade against corruption was being "cheaply brandished" by the new prime minister. "But it should be realized that the undermining of political integrity for personal ambition also lies at the heart of the problem," he declared.

In an attempt to allay fears that the Janata Party was linked with anti-Moslem or anti-Christian factions, Ram announced that members would be forbidden to have links with organizations supporting a theocratic state.

Ram evidently hopes this move will end controversy over the Janata's link with a rightist Hindu chauvinist group. The group, known at the RSS, has been blamed for mucy of the anti-Moslem violence in India, and the controversy over Janata's links with the group was one of the reasons for the downfall of Desai's government.

Ram said that the achievements of the Janata government over the last two years had been "spectacular," but that poorer people had not sufficiently benefited. Also, serious problems of law and order still beset the country, he said.

"The signs of this minority caretaker government crumbling under the weight of its own internal contradictions are already visible," Ram said. "The nation is facing many serious problems and the political system itself has been subjected to serious tensions and strains. This is hardly the time to leave our destinies in the hands of a group whose internal contradictions and a minority character will not allow it to do more than fiddle." CAPTION: Picture, JAGJIVAN RAM,...Indian opposition leader