At the end of 2017, by comparison, 68.5 million people were counted as being forcibly displaced by violence or persecution.

The UNHCR attributed the increase partly to surging displacement in Ethiopia caused by inter-ethnic conflict, and in Venezuela, where thousands are fleeing every day amid an economic collapse that has triggered shortages of basic food and medicine.

An estimated 3.3 million people have left Venezuela since the start of 2016, according to the UN.

UNHCR head Filippo Grandi told reporters in Geneva the figure of 70.8 million only includes Venezuelans who had officially applied for asylum -- roughly half a million people.

Overall, the number of displaced people in the world has doubled over the last 20 years and now exceeds the population of Thailand.

The trend, Grandi said, continues to go in "the wrong direction".

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