The United Nations says the number of refugees worldwide is at a 15-year high and that poor nations are bearing the brunt of the problem.

In a new report being released Monday for World Refugee Day, the U.N. High Commissioner for Refugees says 43.7 million people were forcibly displaced by conflict last year. Millions of others are homeless as a result of disasters such as floods and earthquakes.

Deputy High Commissioner Alexander Aleinkoff says more than seven million refugees have been living in exile for more than five years, while some have been refugees for more than 30 years. He says their prospects for returning home are dim.

The report says many wealthier countries are reluctant to house refugees because of economic problems and religious and cultural differences.

It says this puts the burden on poorer countries, with Pakistan, Iran, and Syria hosting the most number of refugees at the end of 2010.

Pope Benedict Sunday appealed to all nations to be more welcoming to refugees.

Visiting the tiny nation of San Marino, Benedict said refugees need to be guaranteed dignified living conditions until they can safely and freely return home.