A small tent city has formed on Serbia's border with Hungary where migrants are waiting to cross into the European Union despite border closures and a deal with Turkey aimed at stopping more people coming.

Dozens of migrants, including small children, were camping Wednesday in a few dozen tents in a litter-covered field by Hungary's border fence, braving rain and cold nights determined to pursue their dream of a better future in the EU.

"All people want is to cross this border," said 17-year-old Mohamad Idrees from Afghanistan "We must cross this border."

Aid workers say Hungarian authorities have been letting small groups of up to about 20 people a day into the country, mostly families with small children. Still, a few dozen people have been arriving at the border daily and more are expected to arrive with improved weather conditions, raising concerns of humanitarian problems in the makeshift camp

Although the EU and Balkan nations have sought to curb the arrivals after about 1 million people came last year, the flow has continued on a smaller scale, with hundreds crossing one way or another daily, compared with thousands at the peak of the European migrant crisis last year.

On the Serbia-Hungary border, the migrants are facing dire conditions: they have no toilets or showers, and they depend on aid groups for food, drinks and clean clothes. Some women could be seen washing their clothes at the only tap available, while others lit fires for warmth, curling in the small tents among their belongings.

As a van carrying blankets, shoes and socks stopped by the camp, migrants lined up for their share. Some children walked around wearing shoes with no socks amid occasional drizzle; people inside the tents ate from plastic food parcels given out by the aid organizations.

"The situation is pretty inhuman, they don't have hygiene facilities ... they are using the forest as a toilet," said Zsolt Balla, of the United Nations refugee agency. "As summer is approaching, it will easily lead to infections."

Balla said most people at this and another, smaller makeshift camp at the Serbia-Hungary border arrived in the region after the so-called Balkan corridor for migrants officially closed in early March. He described the Hungary crossing as "the legal pathway to the EU" but added that "we see severe difficulties with this route."

"The numbers are changing on a daily basis," Balla said. "We encourage prioritizing the vulnerable people and families — if you look around, many single men are waiting longer than families."

Hungary faced criticism for building a razor-wire fence along its border with Serbia last year to keep the migrants away. Prime Minister Viktor Orban has characterized the migrant influx as an "invasion" threatening Europe's security and Christian culture.

When the Balkan route abruptly closed, thousands of migrants got stuck in Macedonia and Serbia. And when the EU-Turkey migrant deal came into effect on March 20, many others were stranded in Greece. Hungary has reported several hundred people detained trying to cross illegally every week, pushing their way through the fence.

While most migrants at the Horgos border camp are hoping to cross into Hungary legally, many who have faced closed doors have turned to smugglers to guide them over.

Ahmad Samir Zamari, a 20-year-old from Afghanistan, said he is now thinking of going to Croatia with the smugglers after being detained for 13 days in Hungary before being sent back to Serbia.

"What can I do? They said you can't come to Hungary for one year," he complained. "Now I don't know. We don't have any way."

Zamari and other migrants interviewed at the border said they could not return to their home countries, including Afghanistan, Syria and Iraq, because of the wars raging in those countries. Many traveled from Turkey to Bulgaria and then on to Serbia, using more dangerous clandestine routes.

Balla, from the UNHCR, said it is difficult to predict how the numbers of migrants arriving at the border will change in the coming months. He said around 400 people are currently staying at the two makeshift border camps.

A Serbian police officer, who spoke on condition of anonymity because he was not authorized to speak to the media, said numbers have been growing with the spring weather, with many of the new arrivals coming through the new Bulgaria route.

Referring to a camp in Greece where thousands have been stuck for months following the closure of the Balkan route, the officer added that: "I hope this does not become a new Idomeni."