ROME — Pope Francis changed church law on Monday to formally allow women to hold several specific roles during Mass, in a modest but rare step toward more female inclusion in the Catholic Church.

With his decision, Francis gives women the right to act as readers and altar servers, assisting the priest during services or in administering Communion.

Although the move is far from the more significant step of admitting women to the priesthood, Francis said it was a way to recognize that they can make a “precious contribution” to the church.

The new law merely formalizes a role that women in many parts of the world, including the United States, have already been holding. But until now, they had been serving as acolytes and lectors — as the positions are known — at the discretion of local bishops or priests. In some cases, conservative bishops have made a point of enforcing male-only altar services, something they will no longer be able to do.

“Francis, on one side, is merely acknowledging reality on the ground, as it is right now,” said Massimo Faggioli, a professor of theology and religious studies at Villanova University. “But this is important because the [conservative] bishops have been contradicted, openly, by Pope Francis.”

In the riven Catholic Church, the question of how widely to open the door to women has proved one of the most divisive. Although Francis has signaled his preference for a more inclusive church, concrete steps have been rare. He regularly says he considers that only men are fit for the priesthood.

For several years, Francis-appointed commissions have been looking into the question of whether women can be installed as deacons — ordained ministers who can preach and baptize but not conduct Mass. The first commission on the topic effectively dissolved, unable to reach a consensus; Francis established the second commission last year.

Meanwhile, Catholic women’s groups have argued that the church could help itself — and make up for its global shortage of priests — by allowing women to be ordained.

In Germany, a movement of Catholic women has organized church boycotts and asked Pope Francis in an open letter to allow women equal access to positions of church leadership.

Cristina Simonelli, president of an Italian association of female theologians, said Francis’s move Monday was a “minimal thing” but still significant, “if you look at how absurd the situation was.”

“We’re still 100 steps behind the historic moment that we live, but [this is] always better than standing still,” Simonelli said.

Stefano Pitrelli contributed to this report.