By Jeremy Pelofsky
WASHINGTON (Reuters) - The Obama administration has asked a judge in Arizona to dismiss a lawsuit by the state that argues that the federal government has fallen down on the job securing the border with Mexico.
Arizona, led by Republican Governor Jan Brewer, has been in a pitched legal and political battle with Democratic President Barack Obama over efforts to crack down on the flow of weapons, drugs and people across the southwest border.
The state in February sued the Justice Department and Department of Homeland Security for allegedly failing to enforce federal immigration laws or gain control of the American border with Mexico and sought to compel enforcement.
The Obama administration late on Tuesday issued its 35-page response to the lawsuit, denying the allegations in Arizona's suit and saying the state was trying to recast an earlier fight over its a strict law cracking down on illegal immigration that has since been put on hold.
"Arizona repeatedly raises generalized allegations and questions of a political nature, rather than a colorable constitutional or statutory claim," the federal government said in its brief. "This court is not the proper forum in which to air such grievances."
The Obama administration said there is no legal basis to compel the Justice Department and Department of Homeland Security to take action on immigration enforcement and border control, which is left to their "discretion and expertise."
The administration asked District Judge Susan Bolton to dismiss the lawsuit.
Arizona lawmakers last year passed legislation that was signed into law by Brewer that required immigrants to carry legal papers with them at all times and banned those without proper documents from seeking work in public places.
The Obama administration argued that the Constitution gives the federal government sole authority over immigration issues and won an injunction against those key parts of the law. On Monday, an appeals court upheld that injunction.
Arizona officials have complained that illegal immigrants are pouring over the border from Mexico and are enabling drug and weapons traffickers. Obama administration officials have said illegal border crossings have declined.
Arizona's two senators, Republicans John McCain and Jon Kyl, on Wednesday introduced legislation to further improve border security, including deploying up to 6,000 National Guard troops and by 2016 deploying 5,000 more Border Patrol agents.
They also proposed constructing double-layered fencing at some locations and deploying more aerial surveillance drones along the border. The cost of the full plan would be $4 billion and paid for by finding previously unspent government funds.
(Editing by Will Dunham)