The Hungarian government will send buses to transport migrants to the Austrian border, the prime minister's chief of staff, Janos Lazar has said.
The move late on Friday comes as hundreds of mostly Syrian refugees began marching to the Austrian border after being prevented from boarding trains to Germany in the Hungarian capital Budapest.
Authorities appeared to be allowing groups of refugees to make the 170km journey to the border crossing on Friday amid tense scenes across the country.
Al Jazeera's Andrew Simmons, reporting from near the M1 and M7 motorways outside Budapest, said authorities appeared to be helping the refugees make the journey despite fears the road would be blocked.
"There are hundreds of people who have marched something like 10km from the centre of Budapest from the rail station to here...they say they have no option but to do this.
"It may sound far fetched but they're intent on reaching the border.
"The refugees were panicking because they thought the motorway had been blocked off...that road-block was in fact there to help them rather than hinder them."
Simmons said Hungarian volunteers were laying out water bottles to help the refugees marching in sweltering conditions.
Our correspondent said the situation outside Budapest was the "opposite" of what was happening in Bicske, 30km west of Budapest, where hundreds of refugees have broken through police lines and fled after a tense standoff on a train.
Police were able to stop only a minority of an estimated 500 people from leaving the train. Police pushed those they blocked back onto the carriages amid much shouting and screaming and infants crying, the AP news agency reported.
Al Jazeera's Mohammed Jamjoom, reporting from Bicske, said those fleeing were pursued by riot police and at least one man, believed to be from Pakistan, died after the escape attempt.
The group of mainly Syrians and Afghans are refusing to be sent to refugee centres in Hungary and instead want to travel to northern European countries.
"They want to go to other countries, particularly Germany. They do not want to stay in Hungary," Jamjoom reported from the scene of the standoff.
"They are shouting 'No food, no water' as they are in need of supplies. They are also holding signs saying, 'No camp, no Hungary, freedom train'," our correspondent said.
Meanwhile, Hungary shut its main border crossing with Serbia after about 300 migrants escaped from a nearby refugee camp, police said.
"In the interest of preventing accidents, the police have temporarily closed the Roszke motorway border crossing to incoming traffic and are redirecting traffic to (a national road)," police said in statement.
The move came after around 300 people broke through a fence of a nearby refugee camp.
"The police have taken the necessary steps to apprehend them," police said, according to the AFP news agency.
Hungary has become one of the flashpoints in Europe's refugee crisis in recent weeks, as thousands of refugees cross into the country on their way to Germany, which recently eased asylum restrictions for Syrians.
The impasse came as Hungarian politicians prepared to debate tough new anti-immigration measures, including criminalising illegal border crossing and vandalism to the new anti-immigrant razor-wire fence erected along the border with Serbia.
An estimated 2,000 migrants remained sheltered in a concourse underneath Budapest's Keleti station on Friday, waiting for trains to take them towards northern and western Europe.
Hungary's handling of the refugees, who have been stuck for days, sometimes even weeks, in makeshift camps at the station, has caused confusion and anger.
After unexpectedly allowing several thousand to board trains for Austria and Germany on Monday, authorities suspended services for 48 hours, then reopened the station on Thursday, only to have the national railways announce that it was suspending service to western Europe for "security reasons".
|Around 2000 people have been stuck in Budapest after being prevented from travelling to Hungary [Reuters]
Source: Al Jazeera And Agencies