The US Committee for Refugees and Immigrants, which compiled the figures in this year's World Refugee Survey, also said 7.7million refugees had been "warehoused" for five years or more and were unable to work, move or own property in the countries where they were settled.

Survey author Merrill Smith said refugees were guaranteed basic rights, including the rights to move, work and receive an education, under a 1951 UN convention on refugees. However, some large refugee-hosting countries, such as Pakistan and Thailand, had not signed the convention.

"The minimal first step is that they should have every legal right to pursue a livelihood," Ms Smith said.

Many "warehoused" refugees lived in barricaded camps in poor countries, which hosted most of the world's displaced populations.

Nations with per capita incomes of less than $2600 hosted more than two-thirds of the world's refugees, she said.

Oscar-winning actor Angelina Jolie joined US Secretary of State Condoleezza Rice to launch this year's World Refugee Day at the National Geographic Museum in Washington.

"I feel fortunate I can do something good with celebrity ... something much more important than movies," said Jolie, who has served as the UN High Commissioner for Refugees' goodwill ambassador since 2001.

"They are us and often they are the best of us. World Refugee Day is the day ... to commemorate the humanity that binds us all."

The US Committee for Refugees is campaigning to stop the warehousing of refugees, arguing that nations must allow refugees to work, run businesses, own property and have travel documents.

The committee's report includes a grading of countries' performances, and highlights both good and bad behaviour dealing with refugees' rights.

Under the right to earn a livelihood, Chad, Congo, Ecuador, Iraq, the US, Israel, the West Bank and Gaza get A grades for best; Algeria, Iran, Lebanon, Malaysia, Russia and Tanzania receive F grades for worst.

The report says the total number of internally displaced people is 21.3million, an increase of 3.16million since the previous year.

Most of the world's refugees are women, and the report urges the upholding of women's property rights in the context of ending poverty, promoting equality of the sexes, reversing loss of environmental resources and improving the lives of slum-dwellers.