Washington (CNN) - Vice President Joe Biden staked out a middle ground on nuclear weapons policy Thursday, trying to reassure critics claiming the administration's disarmament efforts are either too fast or too slow.
"The spread of nuclear weapons is the greatest threat facing the country - and I would argue facing humanity - and that is why we are working both to stop their proliferation and eventually to eliminate them," Biden said in a 23-minute speech at the National Defense University in Washington.
"But until that day comes, we have to do everything in our power to maintain our arsenal and make sure it is reliable."
The vice president said U.S. nuclear laboratories that monitor the weapons' reliability had been neglected and underfunded in recent years.
"That's why earlier this month we announced a new budget that reverses the last decade of dangerous decline," he said. "It devotes $7 billion to maintaining our nuclear stockpile and modernizing our nuclear infrastructure. To put that in perspective, that's $624 million more than Congress approved last year and an increase of $5 billion over the next five years."
The administration has set out an ambitious nuclear weapons agenda in coming months, with President Barack Obama planning a nuclear proliferation summit at the White House in April.
The United States failed to reach agreement with Russia on a new nuclear arms reduction agreement by the end of last year, when the previous one expired, and those negotiations continue. The administration hopes its boost in funding to safeguard and analyze existing nuclear weapons will win new congressional support for the nuclear test ban treaty that has been awaiting action since 1996.
One arms control analyst warns, however, that the administration may be pushing forward on too many nuclear fronts simultaneously.
"The administration should recognize the relationship of non-proliferation and disarmament is something to achieve sequentially, not simultaneously," said Baker Spring of the Heritage Foundation in a telephone interview. Spring and other administration critics worry that the United States may be unable to respond to future unforeseen threats if it denies itself any chance to test nuclear weapons.
Biden said new technology allows the United States to shift from its Cold War dependence on nuclear weapons.
"Reliance on new and existing conventional weapons will allow the U.S. to reduce its nuclear arsenal," Biden said. "With these modern capabilities, even with deep nuclear reductions, we will remain undeniably strong and in a position to defend our interests against all - all - our enemies."