Croatian authorities have stopped the entrance to that country. A 10-kilometer long line of trucks has formed on the Serbian side.

Serbian Interior Minister Nebojsa Stefanovic has described the move as "unfair and not contributing to good-neighborly relations."

He told RTS that he had not yet spoken with any Croatian officials about this, "as it happened around midnight."

The minister added that Croatia was obviously not dealing with the migrant crisis well.

According to Stefanovic, "it is necessary to find a comprehensive European solution that will say what to do next, how many people can be taken and where to send them."

Stefanovic also stressed that he "does not expect refugees (from the Middle East) to be returned to Serbia - only their transit under certain conditions could be agreed."

The minister stressed that "camps for the return of refugees" will not be built in Serbia.