But many European countries are beginning to curb their own refugee programs, after years of pressure caused by high levels of migration.
Since the arrival of over one million migrants and refugees in Europe in 2015
, governments across Europe have sought to fortify their countries' borders
with fences, walls and guards against future mass migrations.
This month, representatives from 15 countries met to discuss fortifying their borders to make it harder for migrants to reach central and western parts of Europe.
And earlier this year, EU leaders outlined plans to "stem the flow"
of migrants traveling across the Mediterranean from Libya to Italy, and boost the ability of the EU to send people back.
"The key priority is reducing the flow without any consideration for the causes of migration," Dr Nando Sigona, an expert in migration at Birmingham University's School of Social Policy
, told CNN.
"By closing down the routes they are making people even more vulnerable to danger and violence."
Here's how some European countries have been making changes:
UK: Child refugee program halted
The UK government recently announced it was halting a program to resettle lone refugee children, after 350 had been brought to Britain. Campaigners had hoped that 3,000 children would benefit from the scheme, introduced last year.
Home Secretary Amber Rudd told the House of Commons
the government did not want the so-called Dubs amendment to act as a "pull factor" encouraging unaccompanied minors to travel to Europe: "We do not want to incentivize perilous journeys to Europe, particularly by the most vulnerable children."
Alfred Dubs, who came to the UK as a child refugee on the "Kindertransport"
from the Czech Republic in 1939 and who designed the program, expressed his dismay at the decision. "It's bitterly disappointing," the Labour politician told CNN's Christiane Amanpour. "I think they wanted to shut the thing down and found any excuse to do it."
NGO Help Refugees
is taking legal action against the government over their handling of the Dubs amendment. In a statement
, they allege that the Home Secretary's "failure to implement her Dubs duties towards unaccompanied children in Calais ... contributed to [them] being exposed to serious human rights violations." The case will be heard in June.
The government's move is just the latest in a series of measures designed to reduce the number of child refugees eligible to come to the UK.
In November 2016, the Home Office issued new guidance
barring unaccompanied refugees from Afghanistan, Yemen and Eritrea older than 12, who were living in the now-demolished "Jungle" camp at Calais in northern France, from entering the UK if they have no family there.
The following month the government ended the process of transferring children from France after resettling 750 of the 1,900 registered minors
, according to Human Rights Watch. Rudd said she was "proud"
of the UK government's "active approach to helping and sheltering the most vulnerable."
Germany: Asylum seekers returned
More than 250,000 people were given refugee status in Germany in 2016, many of whom had arrived the previous year when Chancellor Angela Merkel threw the country's doors open to refugees, but there are signs that attitudes are hardening.
In accordance with European Commission recommendations, from March, Germany will begin returning asylum seekers to Greece, if that was the first safe country in which they arrived, a spokeswoman for the German Ministry for the Interior told CNN. This process was halted in 2011 due to "systemic deficiencies in the Greek asylum system."
, a German organization that advocates for the rights of refugees criticized the decision
to send "more people into the miserable conditions" in Greece and condemned the transfer system as "inhumane."
A recent report by Amnesty International
highlighted the "dire conditions" in Greek camps, citing "overcrowding, freezing temperatures, lack of hot water and heating, poor hygiene, bad nutrition, inadequate medical care, violence and hate-motivated attacks."
In a further sign of changing views, German Interior Minister Thomas de Maiziere recently announced that border controls with Austria -- introduced as a short-term measure in September 2015 -- would continue indefinitely.
If Europe cannot reliably protect its external borders, De Maiziere said
in a speech, Germany will implement "appropriate national border controls against illegal immigration."
This month, Germany also deported a second tranche of asylum seekers to Afghanistan, despite the UNHCR's insistence that "the entire state ... is affected by an armed conflict."
The European Council on Refugees and Exiles
(ECRE) argues that "by carrying out these deportations, the Federal Ministry of the Interior is completely ignoring the security situation in Afghanistan
Italy: Calls for deportation of migrants
Italy's chief of police, Franco Gabrielli,
has called for the detention and deportation of migrants
, who he blames for "instability and threats" in the country. Gabrielli's comments, published in a circular on December 30, 2016, align closely with the government's position.
Italy's Interior Minister, Marco Minniti, has announced
that one new detention center will be opened in every region, that asylum assessments will be speeded up, and that the ministry will double the funds available for voluntary returns.
The Association for Legal Studies on Immigration
(ASGI) has strongly criticized the proposals
, expressing its "full opposition to the opening of new identification and expulsion centers ... as well as any type of action ... which results in an increase of automatic expulsion orders without adequate assessment of individual situations."
The Netherlands: Election sparks rethink
Dutch Prime Minister Mark Rutte has adopted a zero-tolerance approach to immigrants who are unwilling to sign up to the country's way of life, telling those who "refuse to adapt and criticize our values" to "behave normally or go away."
In the open letter, published on his VVD party's website
, Rutte talked of the "growing discomfort" felt by Dutch people when those who have recently arrived in the Netherlands abuse the freedom that the country offers.
"We must continue to make clear what is normal and what is not normal in this country," he wrote. "We will have to actively defend our values."
The letter echoes his party's election manifesto
, which argues that the current migration system is "untenable" and promises to speed up deportations. The party pledges to invest in caring for refugees in the Middle East in order to reduce the number traveling to Europe.
Center-right PM Rutte is facing a closely-fought election battle with far-right anti-immigration politician Geert Wilders. Wilders was recently convicted of inciting discrimination
Serbia: Newcomers fear being sent back
Several hundred migrants and refugees are currently living in derelict -- and freezing cold -- warehouses in the Serbian capital
Aleksandar Vulin, Serbia's Minister for Labour, Employment, Veterans' and Social Affairs, insists the government has provided facilities for all migrants
in the country.
And Ivan Miskovic, from Serbia's Commissariat for Refugees and Migration, says that the migrants who are living in the depot are there because they have refused to claim asylum
But Amnesty International
researcher Todor Gardos told CNN many of them are "afraid of going to the accommodation centers."
"There is not a functioning asylum system in Serbia and many people are worried they will just be sent back to the border with Macedonia or Bulgaria, which is a real concern," he said.
Hungary: Asylum seekers face detention
The Hungarian parliament introduced a bill on February 14 that requires the police to deport any person who is in Hungary illegally, without allowing any access to an asylum procedure, according to a written statement
by the NGO The Hungarian Helsinki Committee
The bill also requires all asylum applications to be automatically held in detention until their claim is processed, according to the NGO.
The NGO describes the proposed changes as "extreme and flagrant violations of European Union asylum law."
"In the last two months, 1,600 cases of illegal push-backs from Hungary and Croatia have been alleged by refugees and migrants, who've been forced -- often violently -- back into Serbia, despite already crossing its border," the NGO said in a report.
According to the UNHCR, Hungary recently cut the number of asylum seeker applications allowed at its border crossings from 20 per weekday to 10.
"The Hungarian authorities are doing everything they can to keep people out," said Amnesty International's Todor Gardos.
Slovenia: Powers to close border
Slovenia's President recently granted the country's parliament the power "to effectively 'close the borders' if this was deemed necessary due to a serious threat ... caused by migrations," according to the Legal-informational centre for NGOs (PIC)
PIC says the amendment to the country's Aliens Act
means "all persons arriving irregularly and expressing an attempt for asylum would be forcefully returned without their asylum claims being heard."
"We cannot allow a repeat of such mass migrations as we experienced earlier," he insisted at a press conference
. "Our country will help for as long as it has available capacity but then it will have to resort to other measures."
The UNHCR has expressed deep concern about the law, which it says "jeopardize[s] the rights of those fleeing war and persecution to seek asylum."
Poland: Illegal migrants face expulsion
The Polish government has proposed similar changes to those introduced by Slovenia. According to the ECRE
, Poland's draft amendments include "new provisions on border proceedings and the possibility of detention without alternatives."
Introducing the plan, the country's Interior Minister Mariusz Blaszczak said "the main concern is security, followed by sealing the borders, and thirdly the introduction of procedures facilitating the expulsion of people entering -- or trying to enter -- Poland illegally."
The ECRE reports that the Helsinki Foundation for Human Rights
(HFHR) is concerned that some of the changes are contrary to EU law and the European Convention on Human Rights.