Illinois will become the fourth U.S. state to allow illegal immigrants to drive, after the state House of Representatives on Tuesday approved temporary licenses and Governor Pat Quinn said he would sign the measure into law.

Only Washington state and New Mexico allow drivers licenses for illegal immigrants, and Utah provides driving permits.

Supporters of the measure said some 250,000 illegal immigrants already were driving in the fifth most populous U.S. state, and the new law would require them to take a drivers test and have insurance. It was not yet clear how many illegal immigrants would feel comfortable stepping forward to apply for licenses.