WASHINGTON – The Obama administration is developing plans to seek up to 1,500 National Guard volunteers to step up the military's anti-drug efforts along the Mexican border, senior administration officials said Monday.

The plan is a stopgap measure being worked out between the Defense Department and the Homeland Security Department, and comes despite Pentagon concerns about committing more troops to the border – a move some officials worry will be seen as militarizing the region.

Senior administration officials said the Guard program will last no longer than a year and would build on an existing counterdrug operation. They said the program, which would largely be federally funded, would draw on National Guard volunteers from the four border states. The officials spoke on condition of anonymity because the details have not been finalized.

Officials said the program would mainly seek out Guard members for surveillance, intelligence analysis and aviation support. Guard units would also supply ground troops who could assist at border crossings and with land and air transportation.

President Barack Obama earlier this spring promised his Mexican counterpart, Felipe Calderon, that the United States would help with the escalating drug war, which has killed as many as 11,000 people since December 2006.

Earlier this month, Attorney General Eric Holder and Homeland Security Secretary Janet Napolitano announced a 2009 counternarcotics strategy, saying the U.S. would devote more resources to fighting the Mexican drug cartels, including targeting the cash and weapons that flow across the border from the U.S. into Mexico.

But officials say Defense Secretary Robert Gates has expressed concern that tapping the military for border control posts is a slippery slope and must not be overused.

Paul Stockton, assistant secretary of defense for homeland defense, said Monday that options for the new program have been drafted, but the plan still must be approved by key Cabinet members as well as the president.

The administration does not want to announce or begin the effort until after the Mexican elections this week, officials said.

The current National Guard counterdrug operation along the border, which has been in effect for many years, involves about 575 Guard members, who applied for the assignment through their state program coordinators.

The additional volunteers, officials said, would largely be drawn from the more than 50,000 Army and Air National Guard members in Texas, New Mexico, Arizona and California. There are no plans to seek Guard members from other states, although that has not been ruled out.

Lolita C. Baldor,

The Associated Press