The Pope has previously criticised US President Donald Trump’s aim of building a wall to keep migrants out.
The US has put pressure on Mexico’s government to stem the so-called caravans of people from Central America heading north.
“In 2018, six migrant caravans entered Mexico, for a total of 75,000 people. The arrival of other groups was announced,” the Peter’s Pence office said.
“All these people were stranded, unable to enter the United States, without a home or livelihood. The Catholic Church hosts thousands of them in the hotels within dioceses or religious congregations, providing basic necessities, from housing to clothing.”
“In this context, Pope Francis donated US $500,000 to assist migrants in Mexico. This amount will be distributed among 27 projects in 16 dioceses and among Mexican religious congregations that have asked for help in order to continue providing housing, food and basic necessities to these our brothers and sisters.”
In March, the Pope criticised political leaders who tried to erect barriers to keep migrants out.
“Builders of walls, be they made of razor wire or bricks, will end up becoming prisoners of the walls they build,” he said.
The Vatican said Pope Francis had ruled Mr McCarrick’s expulsion from the clergy as definitive, and would not allow any further appeals against the decision.
Martin Bashir, BBC religion editor
This is a significant moment in the Roman Catholic Church’s effort to address the tide of sex abuse scandals – not least because of the high status this former Cardinal Archbishop once held.
Not only was he the first cleric in more than 100 years to resign from the College of Cardinals, but his removal from the priesthood also confirms Pope Francis’ assertion that anyone found guilty of abuse will be treated with zero tolerance, regardless of their status within the church.
The Vatican has said that the investigative process was completed in January and Mr McCarrick was informed of the decision to dismiss him from the priesthood last night. It comes days before Pope Francis will host all the presidents of bishops conferences around the world at a summit in Rome.
The summit is designed to reflect upon the global challenge of abuse and to develop protocols and procedures that could be applied across continents.
What are the allegations?
Mr McCarrick is alleged to have assaulted the teenager while working as a priest in New York in the early 1970s. The claims were made public by the current Archbishop of New York, Cardinal Timothy Dolan.
He said an independent forensic agency had investigated the allegations. A review board, including legal experts, psychologists, parents and a priest, then found the allegations “credible and substantiated”.
Several more men have since said the cleric forced them to sleep with him at a beach house in New Jersey, while they studied for the priesthood as adult seminarians. One man has come forward saying he was assaulted while still a minor.
It has also since emerged that financial settlements were reached in at least two cases of alleged sexual misconduct with adults involving Mr McCarrick.
They involved “allegations of sexual misconduct with adults decades ago”, while he was working as a bishop in New Jersey, bishops in the state told US media.
“It’s your word against God’s” video testimony from three Pennsylvania victims
How does this fit into the wider sexual abuse scandal?
The dismissal of Mr McCarrick is the latest incident in a series of long-running cases of sexual abuse of children and young men by priests at the Church.
Nuns have suffered and are still suffering sexual abuse at the hands of Catholic priests and bishops, and have even been held as sexual slaves, Pope Francis confirmed on Tuesday. The abuse was so severe in one case that an entire congregation of nuns was dissolved by former Pope Benedict.
The scope of the abuse of nuns by clergy members first came to light with the publication at the beginning of February of the monthly Vatican magazine “Women Church World.” The edition included Francis’ own take on the scandal — long known about by the Vatican but virtually never discussed — in which he blamed the unchecked power wielded by priests and higher clergy across the Catholic Church for such crimes.
An Associated Press journalist who first reported on the scandal last year asked Pope Francis on his flight home from the Arabian Peninsula on Tuesday whether enough was being done by the Church hierarchy to address the problem.
The pontiff conceded that it was a problem and said more action was needed. He insisted the will to confront the abuse is there, and stressed that the problem is not new, and that the Church has been working to address it for some time.
“It’s a path that we’ve been on. Pope Benedict had the courage to dissolve a female congregation which was at a certain level, because this slavery of women had entered it — slavery, even to the point of sexual slavery — on the part of clerics or the founder,” the pope conceded.
Alessandro Gisotti, interim director of the Vatican press center, later confirmed to CBS News that the order of nuns dissolved under Benedict was the Community of St. Jean in France. The reason the order was dissolved had not previously been made public.
The Saint Jean order was dissolved in 2005, the first year Pope Benedict served as the head of the Church. He stepped down and Pope Francis took over as pontiff in 2013.
“I would like to underscore that he was a man who had the courage to do many things on this topic,” Pope Francis said of his predecessor on Tuesday.
The pope confirmed that the abuse of nuns was an ongoing problem, but said it was only in “certain congregations, predominantly new ones and in certain regions more than others.”
While the pontiff did not provide further detail on Tuesday, nuns in India and Chile, at least, have previously reported abuse at the hands of priests.
Francis told reporters on his flight that the Catholic Church,” shouldn’t be scandalized by this,” adding that “there are steps in a process,” and “we are working on it.”
The Vatican’s new openness in discussing the abuse of nuns comes after years of revelations about clergy abusing children, mostly boys, in their congregations across the globe, and senior clergy members covering up those crimes.
On his last flight home from an international trip, just last week, Pope Francis warned that expectations for an upcoming landmark Vatican summit on clergy sexual abuse should be “deflated,” as the problem was unlikely to be resolved through it.
The pontiff’s move to lower expectations was likely a disappointment to many Catholics, particularly in the U.S. where the last year has seen a string of revelations about senior church leaders covering up abuse.
Pope Francis has spoken out forcefully against climate change denial. Speaking to reporters Sunday as he flew over Caribbean islands decimated by Hurricane Irma, Pope Francis said humans must make progress in tackling climate change, and called those who continue to deny its existence “stupid.”
Pope Francis: “We will not go backwards, we will go down. That is true. Climate change, you feel the effects, and the scientists tell us clearly the road to take. All of us have a responsibility—all of us—some small, some big, a moral responsibility, to not accept it, to give one’s opinion or to make decisions, and we have to take it seriously. I think it is something we cannot joke about. Whoever denies this must go to the scientists and ask them. They speak very clearly. The scientists are precise. Man is stupid, a head that does not see.”
Pope Francis was speaking with a bandage over his eye because he bumped his head on the popemobile while traveling in Colombia.