Pope John Paul II, in an effort to avert a confrontation between the church and the Mexican government, ordered churches to remain open today in the northern state of Chihuahua, where bishops had planned to cancel Sunday masses to protest allegedly fraudulent elections there two weeks ago.

News of the unexpected papal order was confirmed by a Vatican representative here, Msgr. Jeronimo Prigione. Celebration of the Roman Catholic mass "can never be an instrument of politically motivated pressure," said Prigione, a Vatican apostolic delegate in Mexico.

Last week, in Chihuahua's state capital, Archbishop Adalberto Almeida y Merino issued a pastoral letter announcing that his 62 archdiocesan churches would remain closed today "as a sign of protest, as a loud cry on our part for those whose eyes remain blindfolded or who have been blinded by their own guilt."

The July 6 Chihuahua gubernatorial and municipal elections -- the most bitterly fought state elections in recent Mexican history -- were so marred with fraud that they constituted "a social sin," the pastoral letter said.

Yesterday the archbishop told local reporters that he had received papal instructions to keep Chihuahua's churches open. "We will obey this order," Alemida y Merino said.

"Our denunciation of electoral fraud remains intact, and it is supported by the pope as well, because it deals with a very grave violation of human rights of the kind that the pope has continually denounced with great vigor," the archbishop added.

A Vatican representative could not be reached for comment today on the pope's view of the Chihuahua election conflict.

The unusual papal intervention in a local church-state conflict could be interpreted as a political victory for the Mexican government, which has been the target of extraordinarily direct clerical criticism in recent days. The Chihuahua bishops have attacked what they called the "lies, frauds, and abuse of power" in the elections, while a local priest active in leftist peasant movements has become the featured speaker at antigovernment protest rallies.

Further angering federal authorities, the Chihuahua bishops have joined business groups in backing demands by the opposition National Action Party (PAN from Spanish) that the election be annulled.

As recently as Friday, spokesmen for the Council of Mexican Bishops in Mexico City expressed the hierarchy's full support for the Chihuahua bishops' actions, including the planned cancellation of church services today.

This stance marked a shift in the Mexican church's traditional policy of avoiding overt confrontation with the government. Observers believe that some members of the Mexican church hierarchy were uncomfortable with the unusually public criticism of the elections by the Chihuahua bishops and papal intervention may have reflected that.

Mexico, where 95 percent of the population is at least nominally Catholic, does not have diplomatic relations with the Vatican.

The government-controlled electoral board declared last Monday that the long-ruling Institutional Revolutionary Party (PRI) won solid majorities in the Chihuahua gubernatorial race, in all 14 state legislative districts, and in 65 of the state's 67 city council elections.

Journalists and other independent observers reported seeing dozens of irregularities in the Chihuahua vote. In the most commonly witnessed abuse, accredited opposition poll watchers were barred from stations where early-morning voters subsequently complained that ballot boxes already were filled.

Interior Ministry officials insist that while there were "minor irregularities, there was no grave or generalized fraud" in the Chihuahua contest. President Miguel de la Madrid, following a meeting with PAN leaders Friday, ordered the Interior Ministry to "examine the PAN's assertions in detail."

The stance of the Chihuahua church is construed by Mexican federal authorities as support for the conservative, traditionally Catholic PAN. Such "political activity" by Catholic clerics is "very clearly illegal," a senior Mexican official said Thursday.

High-level Mexican law enforcement authorities responded to the Chihuahua church's challenge by registering complaints in conversations with the Mexico City Roman Catholic hierarchy, said the official, who asked not to be named. "In their actions and in their attitudes, the bishops in Chihuahua have overstepped their bounds," the official said.

Bishop Manuel Talamas Camandari of Ciudad Juarez said that in a discussion last week he pointed out to Interior Minister Manuel Bartlett that Mexican law "recognizes the rights of priests to express political opinions."

Mexican authorities, however, challenge that assertion. Mexico's Constitution, drafted in the intensely anticlerical atmosphere of the 1910-20 Revolution, explicitly prohibits the church from what authorities judge to be partisan political involvement. Priests are constitutionally denied not only the right to hold office, but also the right to vote.

The state holds legal title to church property, including, as progovernment commentators have noted pointedly in recent days, the Chihuahua cathedrals and chapels that the bishops had threatened to close today.

In a conference of Latin American bishops two weeks ago in Bogota, Colombia, church spokesmen said that the Mexican hierarchy has begun "taking a more active position" in protesting the "peculiar" legal restraints on its activities.