Feinstein disagrees with Defense Secretary Robert Gates who says the weapons are needed to protect US security.

“I had a number of classified briefings on it and what I found was that it was essentially a new warhead, and therefore I feared would open the door to nuclear proliferation by others."

The Lawrence Livermore Lab designed the warhead and could win a manufacturing contract if Congress decides to go forward. Feinstein wants to cut nuclear weapons.

“I think the key is bringing down our arsenal as quickly as possible. Nobody needs the number of big nukes that exist in the world today."

Feinstein says the new administration needs to review its nuclear forces before building the warheads.