Pope Francis has pushed back against the “belligerent nationalism” he said has led to claims that Europe is being invaded by migrants crossing the Mediterranean.
The way Europe addresses large numbers of migrants from the Middle East and North Africa has shot up the political agenda since last week, when thousands of people landed on the Italian island of Lampedusa in a matter of days.
The pontiff's call comes as the Lebanese army and civil defence rescued 27 migrants whose boat was sinking off the country’s north coast early on Saturday.
Closing the talks involving bishops and young people from around the Mediterranean, the Pope said that "those who risk their lives at sea do not invade, they look for welcome".
"There is a cry of pain that resonates most of all, and it is turning the Mediterranean, the 'mare nostrum', from the cradle of civilisation into the 'mare mortuum', the graveyard of dignity: it is the stifled cry of migrant brothers and sisters," he said, using Latin terms meaning "our sea" and "sea of death".
According to UN refugee agency, about 178,500 migrants have crossed the Mediterranean to Europe this year, while about 2,500 died or went missing.
Governments in several European countries, including Italy, Hungary, and Poland, are led by outspoken opponents of immigration.
“The solution is not to reject but to ensure, according to the possibilities of each, an ample number of legal and regular entrances,” the pontiff, 86, said in a 35-minute speech that drew a standing ovation from his audience.
“Those who risk their lives at sea do not invade, they look for welcome, for life.”
The Pope said that “as for the emergency, the phenomenon of migration is not so much a short-term urgency, always good for fuelling alarmist propaganda, but a reality of our times”.
Earlier, French President Emmanuel Macron greeted Pope Francis on a wind-swept promenade overlooking Marseille’s old port, and helped him walk into the Palais du Pharo, where he made his speech.
With his wife by his side, the French leader listened as a young Italian volunteer working in Greece and the bishop of Tirana, Albania, who fled to Italy during Albania’s communist rule, spoke of the welcomes they received in foreign countries.
Pope Francis has said his trip is “to Marseille, not France”, and one of his first visits on Friday evening was to the monument to the heroes and victims of the sea.
That had echoes of his first visit as Pope – in 2013 to Lampedusa, where he paid tribute to migrants who had died at sea and condemned “the globalisation of indifference”.
He bemoaned the “fanaticism of indifference” that refugees must endure as they seek a better life.