The United Nations Refugee Agency (UNHCR) has called upon European governments to allow the immediate disembarkation of 507 people recently rescued on the Central Mediterranean who remain stranded at sea.

Many of the stranded migrants are reported to have originated from various African countries, and are survivors of appalling abuses in Libya.

UNHCR says the migrants need urgent humanitarian assistance and should be allowed to access the shores in order to get help.

“This is a race against time,” said Vincent Cochetel, UNHCR Special Envoy for the Central Mediterranean. “Storms are coming and conditions are only going to get worse. To leave people who have fled war and violence in Libya on the high seas in this weather would be to inflict suffering upon suffering. They must be immediately allowed to dock, and allowed to receive much-needed humanitarian aid.”

According to the refugee agency, 151 people remain on board the Open Arms boat, while 356 people more have been rescued in recent days by the Ocean Viking.

UNHCR has called for the European states to take shared responsibility in hosting the migrants after they are allowed to disembark.

Thousands of people have died trying to make the precarious Mediterranean Sea crossing since 2015.

While the numbers have now declined significantly since mid-2017, the central Mediterranean route has remained deadly, with at least 578 people drowning there so far this year according to the UN migration agency.

The latest incident came last month when as many as 150 migrants died in the largest Mediterranean shipwreck of 2019.

The UNHCR is calling for increased search and rescue capacity on the Central Mediterranean, as well as the acknowledgement of the role of NGO boats in saving human lives.