Greek lawmakers prepared to vote on legislation on Thursday that would temporarily halt the processing of asylum applications of people coming from North Africa, a move rights groups have called illegal.

Greece has suspended the processing of asylum applications from North Africa for three months after a surge in migrant numbers. Arrivals by boat from the region will be arrested and detained, conservative Prime Minister Kyriakos Mitsotakis said.

The UN refugee agency (UNHCR) on Thursday raised alarm over Greece’s decision to suspend the submission of asylum applications from people arriving by sea from North Africa, warning it risks breaching international law and undermining the country’s longstanding commitment to protecting those fleeing conflict and persecution.