FORT LAUDERDALE, Fla. — Army Chief of Staff Gen. Ray Odierno is rallying his troops around a common cause: Keep the force ready to fight and reduce costs as the Army begins to downsize over the next five years.

Though confident of the Army’s continued relevance and strength, Odierno said in a keynote speech said the service is teetering on a “razor’s edge.” Speaking Feb. 24 at the Association of the United States Army’s winter conference, he warned that the service is prepared to reduce its ranks by 72,000 troops, as recommended in the president's fiscal year 2013 budget. The cuts would result in an Army of 490,000 active-duty soldiers. But any reductions below that number would not be acceptable, Odierno said.

“That razor’s edge is about balancing readiness, end strength and modernization,” Odierno said.

Looming over the cutbacks is the threat of sequestration, which would automatically cut about $50 billion annually from Pentagon’s budget over the next 10 years. That possibility keeps Odierno up at night, he said. If the cuts are not avoided before being triggered in January, the Army would be forced to cut a further 40,000 to 50,000 troops from the active and reserve components, he said.

“The impact would be profound and across the board,” Odierno said. “Everybody seems to agree it shouldn’t happen, but no one has told me what the solution is.”

Aside from deeper cuts to the Army’s end strength, sequester would put modernization on hold. The service’s efforts to replace its infantry fighting vehicles and upgrade the current fleets of Bradley fighting vehicles, Stryker wheeled vehicles and helicopters would also be threatened, he said.

Odierno said he was satisfied with the president's 2013 proposal.

“We did not lose any major programs, though some of them were slowed down,” he said.

As it stands, the Army is still capable of conducting two wars simultaneously — a strategy Odierno wants to maintain. But another protracted struggle like the Iraq war could overwhelm the force, he said.

“We can fight two Desert Storms if we have to right now,” he said. “What we can’t do is fight two Iraqs that stretch on for eight years.”

Odierno has asked the Army’s Training and Doctrine Command to study the brigade structure. Plans are to reduce the service’s heavy brigade combat teams from 45 to 37, the first two of which will come from Europe.

For the next few months, leaders will study altering the makeup of the heavy brigades to include maneuver battalions and more engineers.

“Those decisions have not been made,” Odierno said. “If we did that, it would represent a further reduction from the planned 37 brigades to perhaps 32.”

If Secretary of the Army John McHugh approves the plan, reorganization of the brigade structure would begin in 2014, Odierno said. The plan would allow the Army to close some regional headquarters it would no longer need, he added.

The Army, meanwhile, will increase the number of special operations forces to at least 35,000, Odierno said. Through the wars of the last decade, including counterinsurgency and anti-terrorism operations, conventional forces have become “inextricably linked” to their special operations counterparts, he said. That is a trend the Army plans to continue as it winds down involvement in Afghanistan and pivots to the Pacific, said Odierno. In that theater, where vast distances favor air and sea power, Odierno sees “a huge role” for land forces.

“There’s lots of ocean out there, but there are also lots of armies,” he said. “There’s a of people who want to put the Army in a box, but it’s the most flexible force.”