Begin resigned in October 1983 and was succeeded as Likud leader and Prime Minister by Yitzhak Shamir. Shamir, a former commander of the Lehi underground, was widely seen as a hard-liner with an ideological commitment both to the settlements in the West Bank and Gaza Strip, the growth of which he encouraged, and to the idea of "aliyah", facilitating the mass immigration of Jews to Israel from Ethiopia and the former Soviet Union. Although Shamir lost the 1984 election, the Alignment was unable to form a government on its own. Likud and the Alignment thus formed a national unity government, with Peres as Prime Minister and Shamir as foreign minister. After two years, Peres and Shamir switched posts. This government remained in power through 1990, when the Alignment pulled out and Shamir stitched together a right-wing coalition that held on until its defeat in 1992 by Labor.