Wichita ? A federal appeals court has delivered a new setback to officials in Arizona and Kansas, ruling that residents in those states can continue registering to vote using a federal form without having to show proof of citizenship.

The ruling is the latest blow to Kansas Secretary of State Kris Kobach, who says the federal form — which requires only that people attest under penalty of perjury that they are citizens — creates a “massive loophole” in the enforcement of laws in the two states. Kansas and Arizona require proof of citizenship in order to keep noncitizens off the voter rolls.

Earlier this month, the 10th U.S. Circuit Court of Appeals in Denver issued a stay of a lower court ruling ordering the U.S. Election Assistance Commission to immediately modify its federal voter registration form to add special instructions for Arizona and Kansas residents about those states’ proof-of-citizenship requirements.

Late Monday, the appeals court extended its block on the lower court order and granted an expedited hearing on the merits of the case sought by the federal commission and voting rights groups.

Kobach has said if the courts do not allow the federal form to be revised, he would implement a system in Kansas allowing people who register using the federal form to vote only in federal races such as for president and members of Congress.

The commission has argued that allowing special instructions on the federal form for Arizona and Kansas would discourage voters from registering for federal elections and would hurt voter registration drives.

Federal election officials and their supporters contend that the federal form provides an important backstop allowing participation of all eligible voters in federal elections, regardless of “onerous” requirements that states may place to vote in their own elections.