South African authorities have issued a warrant for the arrest of former information secretary Eschel Rhoodie on charges of theft and fraud for his role in handling secret government projects, Prime Minister Pieter W. Botha told Parliament today.

Apparently acting to counter growing public doubt about the government's role in multimillion-dollar financial abuses, Botha also ordered investigators to determine whether any minister in his Cabinet knew of the covert funding of a progovernment newspaper or other irregularities by Rhoodie's Department of Information.

Rhoodie, 44, is in self-imposed exile, presumably in Europe.

Suspicions of a government coverup of the growing scandal have intensified this week amid daily allegations in the local press by Rhoodie that at least six Cabinet ministers knew of one or more secret projects he was running. The Cabinet members have all denied any knowledge of the Information Department projects.

The scandal has caused deep concern in South Africa's ruling National Party, which has dominated politics in the white-minority leadership for 30 years. Public confidence in the government is at a low and observers believe Botha will be forced to call an election soon to repair the government party's shattered unity.

National Party infighting reportedly has reached serious proportions, and there are widespread fears that the party's conservative wing may make gains, further complicating efforts to reconcile the races in South Africa.

The latest developments in the scandal were set off by Rhoodie's allegations, which he claims to have documents and tapes to back up. They also come at the worst moment for American and other Western negotiators trying to negotiate a peace settlement between South Africa and guerrillas in the Pretoria-administered territory of Namibia (Southwest Africa).

Foreign Minister Pik Botha today announced that South Africa will attend talks at the United Nations next week that were set up by the United States and the four Western members of the U.N. Security Council. The discussions are aimed at resolving the outstanding issues holding up a peace plan for Namibia.

South Africa's political crisis and the specter of an impending election campaign make it unlikely that the Botha government will be flexible in the "proximity talks" with Western officials and members of the guerrilla group, the Southwest Africa Peoples' Organization.

The move to press charges against Rhoodie comes more than three months after an earlier government report recommended that he be criminally charged. The investigators' report found Rhoodie, former minister of information Cornelius Mulder and the country's former intelligence chief, Hendrik Van den Bergh, solely responsible for the improper funding of the English-language, progovernment newspaper, the Citizen. Rhoodie was directly in charge of the project, which cost the government $36 million.

The delay had caused many people to wonder if the government was not purposefully lax in charging Rhoodie so that he could not contradict the findings of the earlier report, known as the Erasmus Report, at his trial. Rhoodie has publicly challenged the report.

These suspicions were heightened when the police and the government said they did not know where Rhoodie was, but at least two newspapers and his old friend Van den Bergh were able to find him in various countries abroad.

The question now is, how will Rhoodie react? He has already threatened to release details of the secret projects he ran, some of which reportedly involved the bribing of African and Western officials, if the government did not clear his name and unfreeze his financial assets.

In making the announcement in Parliament today, Botha said the Erasmus Commission, which has been investigating the multifaceted scandal behind closed doors since last October, was asked by him now to evaluate the "political culpability" of the government and to report to him by March 31.

This appears to be a maneuver by which the conclusions of the commission report last December can be amended or broadened without suffering loss of credibility. An investigation now into political responsibility may find officials other than Rhoodie, Mulder and Van den Bergh guilty of incompetence or negligence.

This could be politically trouble-some for Botha, whom Rhoodie has implicated in the scandal.

Furthermore, Botha promised Parliament last month that if any member of his Cabinet were found to have knowledge of any of the secret projects he would resign and call an election.

Already there are persistent reports that President John Vorster, who was prime minister while the Information Department projects and other abuses were going on, has offered to resign from his ceremonial post. He has reportedly been asked to stay on, however, as his resignation would cause more problems for the crisis-plagued government at the moment.

Vorster was cleared of responsibility for the Citizen project by the Erasmus report.

Opposition politicians welcomed the move by Botha as a "recognition of the continuing seriousness of the situation," as opposition parliamentarian Zacharias De Beer said. However, they continue to say that the only way to regain public confidence in the government would be to release all the evidence the Erasmus Commision has already heard to a nonpartisan parliamentary committee.

The six-month-old Botha administration has up to now refused to do this, saying that much of the information would be detrimental to South Africa's national interest and to its relations with other states if released.

Some political observers are less charitable of Botha's moves.

"How can you ask a judge to evaluate 'political culpability'? It's like Nixon asking a judge to decide if the Republican administration was guilty during Watergate," complained one Afrikaner.