U.S. Rep. Nathan Deal, a Republican candidate for governor of Georgia, has proposed changing the long-standing federal policy that automatically grants citizenship to any baby born on U.S. soil, a move opposed by immigrant rights advocates.

Supporters of Deal’s proposal say “birthright citizenship” encourages illegal immigration and makes enforcement of immigration laws more difficult. Opponents say the proposed law wouldn’t solve the illegal immigration problem and goes against this country’s traditions of welcoming immigrants.

“This is a sensible, overdue measure that closes a clause that was never meant to be a loophole,” said Bob Dane, spokesman for the Federation for American Immigration Reform, which seeks tighter immigration restrictions.

Under Deal’s proposal, babies born in the U.S. would automatically have citizenship only if at least one of their parents is a U.S. citizen or national, a legal permanent resident of the U.S., or actively serving in the U.S. military.