Greece is working with four other European countries to set up deportation centers in third countries, most likely in Africa, for migrants whose asylum applications are rejected, Greece’s migration minister said Wednesday.

Thanos Plevris said on Greek state broadcaster ERT television that Greece was working with Germany, the Netherlands, Austria, and Denmark for the creation of so-called return hubs, “preferably in Africa.” Ministers from the five countries had already met to discuss the issue, and technical teams would be meeting next week, he said.

“We are not speaking theoretically any more; we are speaking practically,” Plevris said. He didn’t specify which countries were being considered to host the return hubs and said the choice of the African continent was “not binding.” It was the larger European countries that were speaking directly with the countries where the return hubs could be located, “but we are participating too,” he added.