MANAGUA, NICARAGUA, SEPT. 22 -- President Daniel Ortega, adding to a rapid-fire series of recent actions to meet the terms of a Central American peace plan, announced today that the government will create interim rural cease-fire zones and has authorized the Catholic Radio to reopen after a 20-month shutdown.

Shortly after Ortega spoke, Interior Minister Tomas Borge informed a meeting of newspaper and radio directors that the government will no longer censor any media.

The Sandinista government is taking measures in advance of the early November deadline established in the peace plan, signed Aug. 7 in Guatemala by the five Central American presidents, to show it intends to comply fully with the accord, Ortega said.

The new moves coincide with the visit today to Washington of Costa Rican President Oscar Arias, the main author of the Guatemala plan. They are timed, a knowledgeable Central American diplomat said, to strengthen Arias' hand as he seeks to dissuade the Reagan administration from pressing for $270 million in renewed aid for the Nicaraguan rebels, known as contras.

On Saturday, the government gave permission for renewed publication of the opposition daily La Prensa, closed since June 1986. Earlier it freed 16 Central American political prisoners and appointed Cardinal Miguel Obando y Bravo, the Sandinistas' most formidable critic, to head a four-member national reconciliation commission to oversee the accords.

Ortega met for three hours this morning with Obando and other commission members. "I am pleased these positive steps are being taken," Obando said of today's measures.

In a communique, the government said it will begin in coming days to designate zones in the countryside where Sandinista troops will refrain from attacking contra positions, and will be pulled back into garrisons at well-publicized locations.

Ortega described the zones as "a way to arrive gradually" at a full cease-fire mandated by the peace pact to go into effect Nov. 5. (All points of the accord are to take effect 90 days after its signing, or Nov. 5. However, Arias has referred to Nov. 7 as the key date, and some other Central American leaders followed his lead.)

The zones will be declared, Ortega explained, to allow local representatives of the national reconciliation commission to travel to outlying areas without risk of war to propagate the peace plan and "explore the willingness of contra field commanders to accept the cease-fire."

It was the first indication the government will allow the reconciliation commission to talk to contra fighters inside Nicaragua. The government has rejected any direct negotiations with the contras' top leaders, saying it will only speak with their "boss," President Reagan.

In a pastoral letter released last week, the Catholic bishops called on the government to include the contras in talks leading to the cease-fire. But Ortega reiterated today the government will carry it out unilaterally.

Obando indicated the government will soon set a date for an encounter in Nicaragua between the commission and mid-level contras who agree to the terms of the accord, which calls for rebels throughout the region to lay down their arms and accept an amnesty in return for guarantees they can participate in a pluralistic democracy.

Borge's announcement mainly effects a handful of independent radio stations which have been reluctant to broadcast news while prior censorship was in effect, and more than a dozen radios now closed that may seek to return to the air.

Borge said the media can "express any information or ideas without any restriction." However, he noted that a nationwide state of emergency remains in effect. He said it would be the responsibility of editors "not to publish anything which threatens the prospects for peace or tends to destabilize Nicaragua's economy."

The Catholic Radio, the official voice of the Roman Catholic church in Nicaragua, was closed by Sandinista authorities Jan. 2, 1986, after it failed to broadcast a year-end address by Ortega. Its director, Msgr. Bismarck Carballo, was allowed to return Sept. 12 after a 14-month forced exile. Obando said the radio will not return to the air right away because it requires repairs.

{The contras' directorate said the Sandinistra cease-fire announcement would be "positive if it leads to a negotiated end to hostilities" but stressed that a "unilateral and partial" truce would not be effective or credible but must be negotiated with a panel set up by the resistance for that purpose.}