The government of Zimbabwe clamped stringent restrictions today on press coverage of the volatile security situation in this southern African country.

The measure, coming just five days after the government banned entry to foreign correspondents based in South Africa, is expected to curtail severely coverage of military activities in the dissident-plagued southwestern province of Matabeleland.

Prime Minister Robert Mugabe and other senior officials were incensed by widespread western press reports earlier this year of Army atrocities in which more than 1,000 civilians were killed during an offensive against dissidents allegedly loyal to self-exiled opposition leader Joshua Nkomo.

A government regulation published today is apparently designed to end foreign press criticism by using censorship to prevent coverage of the security situation.

The regulation bans publication or transmission of any information on acts of terrorism or sabotage or military efforts to suppress terrorism in areas designated by the minister of home affairs, whose department is in charge of police.

The new measure applies to information "in the press or on radio or television, whether within or outside Zimbabwe."

The act holds both reporters and their editors responsible for violations.

No penalties are spelled out, but government spokesman John Tsimba said resident foreign correspondents who violated the regulations would be expelled.

The only exceptions in the new regulations are for official statements and information cleared by the government or disclosed in parliamentary or court proceedings.

The minister of home affairs has yet to designate any areas where the prohibition applies so, at this point, reporting conditions have not changed, a government spokesman said.

There was little question that the ban would be applied first in Matabeleland, where widespread unrest has resulted from dissident violence and government retaliation.

What areas are designated and when "depends upon circumstances," Tsimba said. The government was preparing itself for potential situations in the future, he added, saying "circumstances could demand designating areas next week or next year."

Tsimba said the government acted because of recent "wild speculation" in the foreign media about new atrocities in Matabeleland. "This is the only way we can control the situation," he said.

British television reported last month that the North Korean-trained Fifth Brigade, which is composed mainly of Mugabe's Shona tribesmen, had killed dozens of Nkomo's Ndebele supporters in northern Matabeleland in June.

Until then there had been a lull in reports of killings by the Army after they reached a peak in January and February.

Dissident attacks have continued unabated, however, with white farmers often the target. More than half of the white-owned farms in the province reportedly are for sale.

The Fifth Brigade, which was allegedly responsible for most of the killings at the beginning of the year, was pulled out of Matabeleland last month, according to western diplomats.

The new regulations are reminiscent of those imposed by the white government of former prime minister Ian Smith in 1978 during the peak of the guerrilla war to attain black-majority rule. Mugabe rescinded the measure after he won power in independence elections in 1980.

The main difference was that under Smith the whole country, then known as Rhodesia, was considered a war zone where reporting on the security situation was banned. Correspondents writing on the war were under instruction to submit their copy to censorship, but the system was hobbled because the manpower-strapped white government did not have enough censors.

Today's regulations also were introduced in the same fashion as under Smith--by invoking emergency powers introduced by the Smith government after it unilaterally declared independence from Britain in 1965 to prevent black rule. Parliament was not consulted in either case.

Today's regulations were issued in the weekly Government Gazette, sandwiched among measures involving distilleries, tobacco marketing and vehicle licenses.

Tsimba said no decision had been taken about penalties for reporters outside the country contravening the new regulations, but most of those reporting on Zimbabwe are based in South Africa and thus already banned by the action earlier this week.

Although journalists frequently report from South Africa on the situation in Zimbabwe, it will be increasingly difficult if the flow of information within the country is cut off.

The ban on journalists based in South Africa, carried out under the auspices of the six "front-line" nations after a meeting last weekend, was accompanied by an invitation to the western media to establish bureaus in black-ruled countries surrounding South Africa. Restrictions such as those imposed today, however, would make the establishment of such bureaus unlikely.

There was little question of the government-controlled press here contravening the restrictions.

The only references to the Army offensive in Matabeleland earlier this year in Zimbabwe's domestic press came in the form of criticism of western media reports.

Earlier in the year the government banned Newsweek's Johannesburg-based correspondent, Holger Jensen, and expelled locally based Manchester Guardian reporter Nick Worrall.