(RNS) — Cardinal Seán O’Malley, archbishop of Boston, and Bishop Robert McElroy of the Catholic Diocese of San Diego have been invited to participate in the Vatican’s Amazon synod, two of three Americans selected to participate in the prominent gathering of Catholic clerics.

The Vatican announced Saturday morning (Sept. 21) that the men will join some 185 voting clerics for the Synod for the Pan-Amazon region, scheduled for Oct. 6-27 in Rome. The other U.S. representative slated to participate is Cardinal Kevin Farrell, operating in his capacity as prefect for the Vatican’s Dicastery for Laity, Family and Life.

The gathering will tackle a variety of issues facing the Amazon region, ranging from political to ecological to the concerns of indigenous people. Bishops are expected to reflect on the synod’s theme, “New Paths for the Church and for an Integral Ecology,” and to address issues affecting the vast Amazon territory that encompasses parts of several South American nations, including Brazil, Bolivia, Colombia, Peru, Guyana, Suriname, Ecuador, Venezuela and French Guyana.

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The region has captured international attention in recent weeks after thousands of fires engulfed parts of the Amazon rainforest, in what experts say is the largest number of fires in the region since 2010.

Both O’Malley and McElroy have been seen as close allies of Pope Francis in the past, although O’Malley has clashed with the pontiff over the last year regarding the sex abuse crisis.

Pope Francis announced the synod in October 2017, singling out the plight of indigenous people he said are “often forgotten and left without the prospect of a peaceful future, including because of the crisis of the Amazon forest.”