Despite considerable opposition to the request, Pope Francis encouraged Bulgarians to welcome migrants into their country during a Sunday speech attended by the nation’s president, Rumen Radev, alongside many other government officials.

"Bulgaria confronts the phenomenon of those seeking to cross its borders in order to flee wars, conflicts or dire poverty, in the attempt to reach the wealthiest areas of Europe, there to find new opportunities in life or simply a safe refuge," Pope Francis said in Sofia after arriving in the Balkan nation for a three-day visit, the Wall Street Journal reported.

"To all Bulgarians, who are familiar with the drama of emigration, I respectfully suggest that you not close your eyes, your hearts or your hands — in accordance with your best tradition — to those who knock at your door," he said at the presidential palace in the capital city.

Bulgaria, the European Union's poorest country, is a popular point for undocumented immigrants seeking to enter the European Union. In recent months, however, the country has asked the EU to close its borders to migrants and has constructed barbed-wire fencing along its border with Turkey to prevent migration.

According to the United Nations, Bulgaria's population is expected to decrease from its current 7 million to a projected 3.9 million by the end of the century due to the nation's high mortality rate, low birth rate and the annual emigration of tens of thousands of its more educated citizens. The country has the lowest average monthly salary within the EU, at about 575 euros ($645), prompting many of its citizens to seek better opportunity elsewhere.

In his speech, the Pope suggested that Sofia work to reverse its population decline, which he described as a "new demographic winter" in the country which has "descended like a curtain of ice on a large part of Europe, the consequence of a diminished confidence in the future," according to multiple reports.

Pope Francis has focused heavily on supporting migrants and refugees during his papacy while the anti-migrant sentiment across Europe remains strong. On Monday, Pope Francis is slated to visit the Vrazhdebna refugee center in the country in a show of solidarity with refugees.

Pope Francis' visit to Bulgaria, which has minority Catholic communities, is also aimed at enhancing relations with the nation's Orthodox Church. On Sunday, the Pope met with Orthodox Patriarch Neophyte, the current head of the Bulgarian Orthodox Church, and also visited an Orthodox cathedral in Sofia.