Pope says repelling, abandoning migrants is 'grave sin'

Pope Francis condemned Wednesday efforts to repel migrants and block their routes as a "grave sin", as he recalled those who lost their lives, including those "abandoned" in the desert.

The 87-year-old regularly calls for more empathy for people fleeing conflict, poverty, disasters or persecution, particularly those seeking to reach Europe from Africa across the Mediterranean Sea.

He dedicated his address at his weekly audience Wednesday to the subject, warning against "restrictive laws" and the "militarisation of borders" and calling for safe migration routes.

"It must be said clearly: there are those who work systematically and with every means possible to repel migrants. And this, when done with awareness and responsibility, is a grave sin," he said.

He repeated that the Mediterranean -- where more than 3,000 migrants went missing last year, according to UN figures -- has become a "cemetery".

"Some deserts too, unfortunately, are becoming cemeteries of migrants. And even here it is not always a question of 'natural' deaths. No," he said.

"At times, they have been taken to the desert and abandoned.

"In the time of satellites and drones, there are migrant men, women and children that no-one must see. Only God sees them and hears their cry."

He did not specify any particular country but said that his description of seas and deserts also includes oceans, lakes and rivers, as well as forests, jungles and steppes "where migrants walk alone".

"Brothers and sisters, we can all agree on one thing: migrants should not be in those seas and in those lethal deserts," he said.

"But it is not through more restrictive laws, it is not with the militarisation of borders, it is not with rejection that we will obtain this result," he said.

He called for "safe and legal" routes for migrants and asylum seekers, and greater international efforts to combat human trafficking.

The European Union admitted in May to a "difficult situation" after a journalism consortium said Tunisia, Morocco and Mauritania were dumping migrants in the desert, using the bloc's funds.

The 27-nation EU has struck deals with the three countries with explicit financing to boost stopping irregular migration to Europe.