MEXICO CITY (Sputnik) - The total number of Venezuelan nationals who have fled the country since President Nicholas Maduro came to power in April 2013 exceeds four million people, local media reported, citing a research company.

Venezuelan newspaper El Nacional reported late on Monday, citing Consultores 21 research company, that the number of refugees, currently amounting to over four million people, could exceed 4.6 million people by the end of 2018, while Venezuelan total population is currently assessed at 31 million.

"Venezuelans' exodus is a humanitarian crisis, and the uncontrolled enhancement of this exodus started in 2016," Marcos Hernandez, the coordinator of the research, said, as quoted by El Nacional.

The authors of the research specified that less than 800,000 people had left Venezuela during the rule of Hugo Chavez, who headed the country from 1999 to 2013.

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According to the UN International Migration Report, released in December 2017, there are 258 million migrants across the world, which makes 3.4 percent of the total world populations.

Earlier in November, the United Nations said that there were three million Venezuelan refugees worldwide, with around 2.4 million of them living in Latin America and the Caribbean.

Venezuela is suffering from political and economic crisis amid a global slump in oil prices, triggered by sanctions imposed by the United States.