Lawmakers who hailed Congress' decision in November to squash funding for two controversial nuclear weapons programs may have to go to the mat once again after indications from the Bush administration that it will seek to revive the program in its 2006 fiscal year budget.

Defense Secretary Donald Rumsfeld has been a proponent of new nuclear weapons research since early in his term. After Congress ignored the administration's prior request of nearly $37 million to continue studying several weapons — including the Robust Nuclear Earth Penetrator (search), or "bunker-buster" bomb, and a low-yield bomb, or "mini-nuke" — officials began quietly looking for ways to restore them.

Earlier last week, the Washington Post reported on a memo Rumsfeld sent to then-Energy Secretary Spencer Abraham about two months ago.

"I think we should request funds in FY06 [fiscal year 2006] and FY07 to complete the study. Our staffs have spoken about funding the Robust Nuclear Earth Penetrator (RNEP) study to support its completion by April 2007," Rumsfeld wrote in the Dec. 10, 2004, memo.

While the memo may have surprised anti-proliferation lawmakers and activists, the bombs have for some time been out in the field, though one has yet to be used, an Energy official who asked not to be named told FOXNews.com.

The RNEP, a B61 or B83 nuclear bomb enclosed in an extra-hard casing, currently can tunnel through the earth no more than 30 feet and has never been tested. A bunker-buster that can't get more than several hundred feet below ground would require a yield 10 times greater than that of the bomb dropped on Hiroshima in 1945 in order to destroy a target buried more than 1,000 feet deep.

The Pentagon wants to keep funding the programs to see if a heavy-load, deeper-penetrating nuclear weapon can be made. Many prominent scientists insist that the casing material needed for the bomb to pierce hundreds of feet of rock simply does not exist.

Rumsfeld's letter indicates that the administration will tuck new funding for the research programs into its fiscal year 2006 budget request on Feb. 7. Such a request is likely to meet serious resistance from lawmakers opposed to the programs — a group led by Rep. Dave Hobson, R-Ohio, who holds the post of House Energy Appropriations Subcommittee chairman.

But officials at the National Nuclear Security Administration (search), which oversees the programs, have left open the possibility of trying to go around Hobson and his colleagues on the subcommittee by shifting funding responsibility to the Pentagon.

In a December panel discussion sponsored by the Washington-based Arms Control Association, NNSA director John Harvey was asked whether the administration would go that route.

"Look, anything is possible," Harvey said. "But let me tell you something. You'll get me into the biggest trouble I can get [into] if you start trying to get me to forecast what the president is going to do in the budget."

A shift in funding authority is extremely rare in Washington, D.C., and would be a clear signal from the White House that it plans to pursue the new weapons research aggressively.

"Members of Congress, and chairmen of committees in particular, jealously guard their jurisdictions. Chairman Hobson will not look kindly on this move and he is unlikely to passively accept it," said Joseph Cirincione, director of the Non-Proliferation Project (search) at the Carnegie Endowment for International Peace.

"He will probably find support from others, even those who agree with the program" out of fear it will set a precedent, Cirincione told FOXNews.com

While officials were not willing to comment on such maneuverings, a Pentagon spokesman dismissed the notion that Rumsfeld was secretly strong-arming the Energy Department over the matter.

"Defense is not dictating to Energy — we are supporting them. That's a huge difference," Maj. Paul Swiergosz told FOXNews.com.

Of course, moving the programs to the Defense Department's budget is no guarantee of approval.

"If funding for the bunker-buster is included in President Bush's budget, I will once again fight to kill this program," Rep. Edward J. Markey, D-Mass., said in a statement to FOXNews.com.

Should the administration decide to stick the funding under the Defense Department, the task of approving the request will be overseen by Sen. Ted Stevens, chairman of the Senate Defense Appropriations Subcommittee, and Rep. Bill Young, R-Fla., who will likely be named House Defense Appropriations Subcommittee chairman next week. Neither Republican congressmen could be reached for comment.

Hobson declined to comment on any speculation before the administration submits its budget. But in a speech to the Arms Control Association (search) on Thursday, Hobson reiterated his belief that "we are fighting too much of the last war on the nuclear weapons front and not paying enough attention to the developing front of nuclear terrorism."

Hobson in the past has been supportive of RNEP research, but last year's NNSA estimate that it would need nearly $500 million to fund the program through 2009 alarmed him so much he removed the program's funding. The Ohio Republican has said the administration hasn't given him a sufficient explanation for why so much funding should be allocated for a weapon it says won't be produced.

While Hobson's previous actions indicate he would fight a new request for funding the programs, he said on Thursday, "I am impressed by all the good things I have heard about the new secretary of energy, Sam Bodman (search), and I look forward to working with him on all of these issues."

A fresh go at re-establishing funds for the research programs could set up a battle between Hobson and Republican Sen. Pete Domenici, who chairs the Energy and Natural Resources Committee in the Senate and is a senior member of the Appropriations Committee.

Domenici, whose state of New Mexico is home to Los Alamos National Laboratory (search) and Sandia National Laboratories (search), is a powerful advocate for the research programs. Critics contend that having two of the three government-run weapons labs in his state has made him a lobbyist for any new nuclear research funding.