(CNN) -- Some 2 million Iraqis have fled their country, most seeking refuge in Syria and Jordan, and another 2.4 million have been displaced inside Iraq, according to the United Nations.
The head of the U.N. refugee agency is on the road this week in the Middle East, trying to drum up more world support for a people in "desperate" straits.
Antonio Guterres, the U.N. High Commissioner for Refugees, traveled Tuesday to Jordan, where he met with King Abdullah II and thanked him for hosting the displaced. He also met with refugees and government ministers.
Guterres traveled to Syria on Thursday to meet with refugees, aid workers and officials.
Ron Redmond, Guterres' spokesman, said Guterres had been in the region about a year ago and returned to review programs addressing public health, food, shelter, education assistance and refugee resettlement in Syria and Jordan.
"He wanted to come back here and assess the programs and highlight the need for more international attention to the plight of more than 2 million Iraqis," Redmond said, referring to the programs as a "pretty massive" effort.
Iraq has had the most significant population displacement crisis in the Middle East since the founding of Israel in 1948.
The U.N. refugee agency has appealed for $261 million for programs to support refugees and internally displaced people. The crisis has received international attention from politicians, humanitarian workers and even celebrities such as actress Angelina Jolie, who was in Baghdad, Iraq, last week in her role as a UNHCR goodwill ambassador.
"There's certainly much more awareness than there was a year and a year and a half ago toward this problem," Redmond said.
Population flight has been occurring for years, but the situation worsened after a bombing of a Shiite shrine in Samarra unleashed sectarian warfare two years.
Sunnis, Shiites and Christians fled Iraq to cities like the Syrian capital of Damascus and the Jordanian capital of Amman. There are 1.4 to 1.5 million Iraqis in Syria and 450,000 to 500,000 in Jordan.
"It's an exodus that took place rather out of sight," Redmond said. "These Iraqi refugees are living in an urban environment where, to outsiders, it's not all that obvious," and generally, they are "not in big sprawling camps."
"Now, however, [the Syrian and Jordanian] governments are really struggling to cope with the huge number of people in these cities," he said.
The UNHCR is making a push for the world community to help ease the burdens the refugee influx has placed on those nations. Redmond said there is an agreement in the works to bring in more nongovernmental organizations into Syria to address refugee problems.
"The amount of assistance that is being provided to them and their governments is minuscule compared to the problem," Redmond said, calling the $261 million a "drop in the ocean compared to their needs."
Even though 46,000 Iraqis returned from Syria between September and December amid news of improved security in Iraq, according to agencies such as the Iraqi Red Crescent, the problem of the displaced remains significant.
The February UNHCR "Syria update on Iraq refugees" says "the return movement to Iraq that increased immediately after the imposition of new visa regulations appears to have subsided."
A U.N. survey of 110 Iraqis in Damascus in November asked why they, or people they knew, were returning to Iraq.
According to the report, "46.1 percent of respondents answered that they could no longer afford to live in Syria. 25.6 percent answered that people's visas had expired and they were forced to leave. 14.1 percent had heard that the security situation had improved and that they could go home."
Life is becoming "more and more desperate for these people as time goes on," Redmond said. Citing the country's instability, he said the UNHCR doesn't believe that there should be a large-scale return to Iraq at this time and is not encouraging such a move. E-mail to a friend
CNN's Joe Sterling contributed to this report.