Officials said the dramatic statistics meant additional resources needed to be given to countries handling the influx of migrants.
“These alarming figures highlight the urgent need to support host communities in the receiving countries,” said Eduardo Stein, a UN special representative for Venezuelan migrants, in a statement.
“Latin American and Caribbean countries are doing their part to respond to this unprecedented crisis but they cannot be expected to continue doing it without international help.”
Migration from Venezuela has mostly affected Latin American countries, with bordering Colombia accepting nearly 1.3 million Venezuelans, followed by Peru, which has accepted at least 768,000, according to the report.
Chile, Ecuador, Brazil and Argentina are also reportedly hosting a combined 1.6 million Venezuelans, while countries across Central America and the Caribbean are also said to have taken in significant numbers of migrants.
The latest migration figures from Venezuela were announced on Friday by the United Nations High Commissioner for Refugees, along with the United Nations Refugee Agency and the International Organisation for Migration.
Venezuela has endured a crisis in its economy and its leadership, with President Nicolas Madurofacing international calls to resign after accusations of rigging in the 2018 election.
Meanwhile, nationwide shortages of basic goods have fuelled a financial collapse, and the country has seen sharp reductions in oil production.
Eight out of 10 Venezuelan migrants are now in countries across Latin America and the Caribbean, according to the Council on Foreign Relations.
The council had previously reported in March that over 2.7 million people had fled the country due to issues including food and medicine shortages, hyperinflation and crime.
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