The Israeli cabinet on Sunday approved a plan to expel 400 children of foreign workers in Israel, who now must leave by the end of the month. The government claimed the move was a bid to stem illegal immigration across Israel’s porous southern border with Egypt and to safeguard the country’s Jewish character.

One Israeli advocacy group, the Hotline for Migrant Workers, estimated that as many as 700 of 1,200 school-age children are at risk of deportation.

Israel is home to about 200,000 migrant workers, mostly from the Philippines, China and Africa, half of whom have overstayed their visas. Hundreds of them are brought each year to Israel, where they work as cleaners, construction or farm workers or caregivers for the elderly.

Under the plan, only children of parents who entered Israel legally may be eligible for permanent residency. They must be enrolled in school, speak Hebrew and have been either born in Israel or entered it before age 13. Also, they must have lived in Israel for five consecutive years, which means that children younger than five are likely to be expelled, as well as those who had returned for a period to their country of origin.