A record 65.6 million people are either refugees, asylum seekers or internally displaced across the globe, the UN refugee agency said.
The estimated figure for the end of 2016 is an increase of 300,000 on 2015, according to its annual report.
It is a smaller increase than 2014-15, when the figure rose by five million.
But the UN high commissioner for refugees Filippo Grandi said it was still a disheartening failure of international diplomacy.
"The world seems to have become unable to make peace," Mr Grandi said.
"So you will see old conflicts that continue to linger, and new conflicts erupting, and both produce displacement… forced displacement is a symbol for wars that never end."
In 2016, some 340,000 people fled the violence in South Sudan into neighbouring Uganda. That was more than any other country - even more than the 200,000 people estimated to have fled Syria.
The UN said it hoped Monday's record breaking numbers of displaced would encourage wealthy countries to think again: not just to accept more refugees, but to invest in peace promotion, and reconstruction.
Mr Grandi also warned of the burden being placed on many of the world's poorest states, as some 84% of the world's displaced people are living in poor and middle income countries.