Israel’s government has decided to close the Holot migrant detention facility in the Negev desert as part of a crackdown on the country’s illegal migrants originating from Africa.

Instead of being kept in open detention, those without a legal residence permit will be given the choice of going to prison indefinitely or being deported to Rwanda.

The government claimed the new policy, which attracted support from sections of opposition parties Labour and Yesh Atid, was moral and confirmed to international law.

There is no certainty in Israel on how many foreign citizens are currently living without a legal permit.

An estimated 40 thousand refugees from Sudan and Eritrea are claiming to be political asylum seekers, but the government insists they are work migrants.

The African migrants have been in the country for at least five years, arriving on foot through the Sinai Desert before a new border fence was completed in early 2013.

Most live packed into apartment blocks in the working-class neighbourhoods in South Tel Aviv, where they find support only from a few left-wing MPs and a handful of charities.

Israel has an agreement with Rwanda, which will accept migrants at $5,000 (£3,760) a head, concluded after an earlier agreement with Uganda fell through.

The few thousand migrants who have so far voluntarily agreed to go to Rwanda have each been given $2,000 each, but it is still unclear whether this arrangement will hold for the tens of thousands still remaining.

Even if the Africans are all deported at a cost of a quarter of a billion US dollars, unknown numbers of migrants from the former Soviet Union will remain.

Immigration experts believe there are much larger numbers of Russian, Ukrainian and Georgian citizens living illegally in Israel, but critics say they are less obtrusive because they are white and live among the Russian-speaking communities around the country.

The closure of Holot comes as Israel confronts some of the most sweeping demographic changes in its history. With over eight million citizens, a relatively high birth-rate and an attractive quality of life, it is rapidly becoming comparable to many countries in Europe.

This has attracted migrants from poorer parts of the world looking for a new life, but Israel remains a special case because it is locked in a complex demographic balance with the Palestinian population. There is no standard naturalisation process in the country either, apart from the Law of Return that allows Jews and their family members to emigrate.

With unemployment at an all-time low and Israeli business already employing over fifty thousand Palestinian workers with daily work-permits, supporters believe the Israeli economy could easily absorb the African migrants.

But allowing the Africans to work legally in Israel would mean changing the country’s immigration laws and opening an avenue for large numbers of non-Jews to move to Israel. For the moment, that remains a political taboo.