Archbishop Timothy Broglio of the Archdiocese of the Military Services, USA, president of the U.S. Conference of Catholic Bishops (USCCB), congratulated the 21 new cardinals, including two from the United States, recently appointed by Pope Francis, a USCCB press release said.

The U.S. appointees are Archbishop Robert Prevost, Prefect of the Dicastery for Bishops, a native of Chicago, and Archbishop Christophe Pierre, the Apostolic Nuncio to the United States, the USCCB release said.

“Please join me in praying for Cardinal-designate Prevost and Cardinal-designate Pierre as they continue their lives of service to the universal Church,” Broglio said in the USCCB release. "For the Church in the United States, their ministry has been a true blessing. Our episcopal conference rejoices in this sign of recognition of these distinguished Churchmen.”

Prevost and Pierre are to be ceremoniously elevated on Sept. 30. The rank of cardinal is the second-highest rank within the Church, behind only the pope. The list of newly appointed cardinals includes a group of archbishops, bishops, and fathers from nations including Italy, Argentina, Venezuela, Poland, Spain, South Africa and others.

"Congratulations to all, in particular to Cardinal-designate Prevost, a former member of @cmsmtweets, and to the Apostolic Nuncio to the United States of America, Cardinal-designate Pierre," Fr. Frank Donio, founding director of the Catholic Apostolate Center, said in a tweet.

Since becoming pope in 2013, Pope Francis has named 121 cardinals from more than 60 countries, accounting for approximately 67% of all appointed cardinals during his tenure, the Catholic News Agency said.

The significant percentage of cardinals chosen during Pope Francis' tenure can be attributed to the fact that several cardinals have reached the age of 80. As a result, Pope Francis has found it necessary to make additional appointments to maintain the current size of the College of Cardinals, the Pillar said in a news story.

Pope John Paul II is the pope who has named the largest number of cardinals, as 40 voting-eligible cardinals were appointed under his papacy. The second-largest consistory in terms of new cardinal appointments took place in 1969 under Pope Paul VI, when 33 cardinals were added to the College, the Pillar reported.

"Thank you, Pope Francis, for giving Southern Africa a second Cardinal so that the voice of the Church in this Region will continue to be heard," Cardinal Wilfrid Napier of South Africa, said in a tweet. "Congratulations to Cardinal Elect Stephen Brislin. God be with you even more strongly!”