German Chancellor Angela Merkel, French President Francois Hollande and Greek Prime Minister Alexis Tsipras are meeting in Brussels on Friday to discuss the inflow of migrants in Europe, which may back up in Greece as the main route to Europe is slowly shut down.
Greece is likely to be at the forefront of the talks, after the European Union last week issued steps that Athens should implement to better control its borders within the next three months.
In January, Austria decided to limit the number of asylum seekers, setting off fears that other countries upstream on the so-called Balkan route - the main route to Northern and Western Europe for migrants - will become backed up.
Balkan countries are already following Austria's cue for heightened border security, with plans to stop migrants at their borders, despite growing worries that this could lead to a humanitarian crisis in Greece as refugees continue to flow in and become stranded there.
Hungary said it will seal the three railway crossings it shares with Croatia starting February 21 "in the interest of public security," according to media reports Friday. The measure will be in effect for 30 days.
Hungary was on the path of migrants arriving through Serbia and Croatia until it sealed its borders with the two countries in September and October.
The leaders of the three countries may also discuss the financial crisis at Friday's meeting, diplomats have said.