(Reuters) - The United Nations refugees' agency on Wednesday said restrictions imposed by western Balkan states on the movement of migrants fly in the face of basic refugee protection rights. Filippo Grandi, who heads the United Nations High Commission for Refugees (UNHCR), said the move may stifle movement and create a bottleneck of migrants and refugees in Greece, which has until now been the primary gateway of people fleeing conflict from the Middle East. "(These) restrictions probably go against even European rules and regulations and certainly against basic refugee protection laws," he told reporters in Athens.