VATICAN CITY: Pope Francis said on Saturday he realises some people, including within the Church, consider him to be "a pest" for defending the poor and most vulnerable, but that it won't stop him as it is part of Christianity.

"Thinking about these situations (of exclusion and inequality), I make a pest of myself with my questions. And I go on asking. And I ask everyone in the name of God," said Francis, Latin America's first pope.

He called on pharmaceutical companies to release patents to make vaccines for COVID-19 more available to the poor, noting that only 3%-4% of the population in some countries had been vaccinated.

Francis, 84, was speaking by video link to the World Meeting of Popular Movements, a grouping of grassroots organisations and social movements which bring attention to inequality in labour, land ownership, health care and other social issues in the developing world.

He called on industries such as mining and lumber, "to stop destroying forests, wetlands and mountains, to stop polluting rivers and seas, to stop poisoning food and people".