Washington (CNN) -- Congress should proceed on immigration reform while the administration strengthens security at the southwestern border, a top U.S. official said Wednesday.
"The border is as secure now as it's ever been," said Homeland Security Secretary Janet Napolitano. "You're never going to totally seal the border."
"The notion that you're going to somehow seal the border and only at that point will you discuss immigration reform -- that is not the answer to the problem," the secretary said during a speech at the Center for Strategic and International Studies.
Last week, Arizona Republican Sen. Jon Kyl told a Tea Party town hall that President Barack Obama had told him during a private meeting that Congress would have no reason to support immigration reform "if we secure the border." The White House denied Kyl's version of the meeting.
Napolitano said the federal government should set immigration and border security policies.
"We need a single, functional immigration and border policy," said Napolitano, in a clear reference to Arizona's new immigration law that requires law enforcement to check the papers of anyone they're investigating if they suspect that person may be an illegal immigrant. "We cannot have 50 different state policies. It simply will not work for us."
Napolitano would not confirm reports that the Justice Department planned to file suit against the law.
Earlier this month, Secretary of State Hillary Clinton told a Latin American TV network the Justice Department would sue, but the department said only that the law remains under review. Privately, however, administration officials have said a suit is planned to stop the measure from going into effect July 28.
Napolitano discussed some new steps to secure the southwest border, including a program to increase manpower by having non-border state law enforcement agencies detail officers to border states. The Department of Homeland Security also is working on an initiative with the Justice Department that would create a new system to link the information systems of state, local and tribal law enforcement groups operating along the border with those of Justice and Homeland Security
Napolitano also said Immigration and Customs Enforcement is expanding its efforts to identify convicted illegal immigrants in U.S. jails and deport them.
On Tuesday, Obama asked Congress for $600 million in emergency spending to step up border security. The money would pay for the hiring of 1,000 new border patrol agents, 160 new Immigration and Customs Enforcement agents, two unmanned aircraft systems and other efforts. The president said he would offset part of the cost of the new programs by cancelling $100 million dollars from a lower priority Department of Homeland Security program.