In matters of policy and perceptions, the smallest maneuvers can be held out as significant. In this vein, conservative backers of rebels fighting in Mozambique are pointing to a meeting last week with a top administration official, Frank C. Carlucci.

The rebel backers are working to force a change in the administration's policy of favoring the Marxist government there and refusing to help, or recognize, its anticommunist opposition.

Last Wednesday, the rebel supporters said, they arranged a meeting with Carlucci, the president's national security adviser, at which a representative of the rebel Mozambique National Resistance, known as Renamo, was included in the discussions.

Carlucci took an hour out of his busy schedule -- just a day before the formal announcement of his nomination as secretary of defense -- to meet with six conservative lobbyists for the Renamo cause.

Among the six was Thomas W. Schaaf Jr., who is executive director of The Mozambique Research Center, the main lobbying group for Renamo here. Schaaf is a U.S. citizen, but he lived in Zimbabwe for many years and has traveled extensively inside Mozambique.

Carlucci is the highest-ranking administration official known to have met with a representative of Renamo here.

There were sharply conflicting views afterward as to the significance of the meeting and whether Carlucci was even aware there was a Renamo representative in the room.

The conservatives portrayed it as a victory for the Renamo cause and believe, as one put it, that there already has been "a 90 percent change" in the administration's attitude toward Renamo.

"We are with Mozambique today where we were with Savimbi and Angola three years ago," said Grover Norquist, one of the six who met Carlucci. He was referring to Jonas Savimbi, whose National Union for the Total Independence of Angola (UNITA) has been receiving administration political backing and covert military aid since early 1986.

White House officials, on the other hand, played down the meeting and said it was simply a session arranged to listen to the views of the administration's conservative supporters on various issues, including Mozambique.

One U.S. official said it was "totally false" and "a gross exaggeration of the truth" to say Carlucci had met knowingly with a Renamo representative or that the meeting signaled a shift in administration policy toward recognition of the rebel group.

"The idea there would be a Renamo representative was a total surprise," said the official. "He {Carlucci} was not meeting him as a Renamo representative but as a conservative supporter of the administration."

The official deemphasized the importance of the Renamo issue in the discussions, saying President Reagan's Strategic Defense Initiative (SDI) had taken up at least half of the time.

However, two of the conservative lobbyists participating in the meeting gave another version.

Neal Blair, president of Free the Eagle, said "it {the meeting} was specifically to talk about Renamo, that was the understanding."

Blair said he had told Carlucci's office beforehand of "everyone who was coming," including Schaaf and what group he represented.

Also attending the meeting were Paul M. Weyrich, a New Right leader and president of the Free Congress Research and Education Foundation, and William Pascoe, a policy analyst at the Heritage Foundation.

Norquist, a foreign policy adviser to Republican presidential candidate Pierre S. du Pont IV, concurred with Blair's understanding. He also said Carlucci had assured the group that if Mozambique's president, Joaquim Chissano, did not move soon toward opening negotiations with Renamo, the administration's attitude toward him would change.

Chissano met with Reagan at the White House Oct. 5. The prospects for a negotiated settlement of the conflict through some kind of dialogue between the government and Renamo was a main topic of their conservations, according to U.S. officials.

"We were assured we would see movement by Jan. 1 or the United States would reconsider its position," Norquist said.

White House officials did agree with the conservatives' account of their meeting with Carlucci on at least one point, namely that Reagan had extracted a promise from Chissano of a change in attitude toward negotiating with Renamo.

Chissano agreed that a political solution had to be found through "some sort of arrangement" with Renamo and wanted "some kind of U.S. help" to achieve this, they said. One White House official described Chissano's change in atttiude toward reaching an accord with Renamo as "the main thing" that came out of his meeting with Reagan.

The official noted that the United States helped to broker indirect talks in South Africa between the government of Mozambique and Renamo in 1984, even though they failed to produce any results. It would not be "unprecedented," the official said, for the administration to have "contacts {with Renamo} that help lead to negotiations."