WASHINGTON - President Bush on Tuesday signed legislation ensuring that children born to American parents outside the United States don’t lose their place in line for permanent residence status when they turn 21.

Foreign-born children under 21 are supposed to get immediate consideration for visa petitions. But if the Immigration and Naturalization Service, because of backlogs, doesn’t begin processing the petition until after the applicant becomes 21, the person is shifted to a different category and the application process can be extended for years.

Under the new measure, passed easily in both the House and Senate, the immediate relative status is determined when the application is made, not when the INS begins processing it.