GROTON, Connecticut — Budget cuts must not be allowed to undermine the US military's industrial base, Defense Secretary Leon Panetta said Thursday during a visit to a shipyard that builds attack submarines.

Panetta used his stop at the Electric Boat shipyard in Groton, Connecticut to underline the importance of preserving the know-how of the country's defense industry that he said was jeopardized by potential sweeping cuts in military spending.

"We cannot have a strong defense for the United States without protecting this industrial base," Panetta told a crowd of about 200 workers in hard hats.

"I need to be able in this country to produce our ships, to produce our submarines, to produce our planes, to produce our fighter planes, to produce our tanks, to produce what we need for the military.

"I don't need to rely on another country. We've got rely on the United States to do that," he said to cheers, with an imposing Virginia-class submarine behind him.

The defense chief said the specialized skills of those building submarines or other weapons could not be easily replaced and might be lost permanently if deeper cuts go forward due to political deadlock in Congress.

"You too are the patriots that I need to depend on. Your skills, your capabilities, what you're able to do, that is an important resource that we have to protect for the future," he said.

Before he spoke, Panetta got a tour of the soon-to-be commissioned Mississippi fast attack submarine, which manufacturer General Dynamics says has been produced a year ahead of schedule and under budget.

The US Navy has eight of the nuclear-powered Virginia-class vessels and plans to build at least 30.

The submarines, which cost more than $2 billion each, are designed to strike enemy subs, launch Tomahawk cruise missiles, gather intelligence and deliver special operations forces.

While commanders see the Virginia-class submarines as an important counterweight to anti-ship missiles being developed by China and other states, the Navy faces budget pressures that could mean scaling back plans for the future fleet of fast attack subs.

The Pentagon is already preparing for more than $450 billion in cuts over the next decade, but political stalemate in Congress could mean roughly another $600 billion in additional reductions.

Panetta this week warned that if Congress fails to prevent deep defense budget cuts, the US military will be left weaker, slower and smaller.

He outlined on Monday the potential effects of automatic cutbacks should a congressional "supercommittee" fail this month to reach a deal to reduce the country's deficit, painting a dire picture.

Panetta, a former lawmaker and White House budget chief under former president Bill Clinton, said at the shipyard on Thursday that members of Congress needed to "suck it up" and show leadership on the deficit, saying the problem could not be solved without tackling mushrooming spending on so-called entitlement programs as well as raising tax revenues.

"You want to fix these deficits, you got to make the same damn decisions" that were made in budget deals in the past, he said.

"So I really urge leaders in Congress, I urge this (super) committee -- suck it up, do what's right for the country," he said.

"That's why we elect people, to govern. Not to just survive in office."