JERUSALEM — Amid mounting concern in government circles here over the long-term impact of large numbers of foreign workers living in Israel, Prime Minister Benjamin Netanyahu has vowed to take drastic action against them.

Labor Minister Eliyahu Yishai presented the Cabinet Friday of last week with a plan to cut the number of foreign workers drastically. The plan calls for the deportation of 100,000 illegal foreign workers and a reduction in the number of legal workers by 20,000 during the next 18 months.

Some 100,000 workers from Europe, Asia and Africa were allowed into Israel to replace Palestinians whose entry was prohibited after the closure was imposed earlier this year on the West Bank and Gaza.

Between 100,000 and 150,000 additional foreign workers are in Israel illegally.

The Interior and Labor ministries have warned that if the number of foreign workers is not cut down immediately, Israel may face monumental social problems, similar to those faced by France and Germany. Those countries have large transient communities of workers who seek to become permanent but are not entitled to citizenship.

Meanwhile, the Netanyahu government has in recent weeks eased the closure of the West Bank and Gaza Strip to allow some 35,000 Palestinians to enter Israel daily for work, which in effect lessens dependence on the foreign workers.

The ban on Palestinian workers came last winter, after a series of suicide bombings by radical Palestinian groups.

Yishai recommended setting up a new foreign workers authority, which would establish detention centers in which the workers would be held until they are deported.

The proposal sparked an attack by MK Amnon Rubinstein of the leftist Meretz Party.

"I envision the outcry once those camps are erected," he said. They will be seen as an "inhumane act which will hurt Israel's image."