Schultz was the longest serving secretary of state since World War II and had been the oldest surviving former Cabinet member of any administration. The former Marine Corps artillery officer was 100.
The treaty limits each country to no more than 1,550 deployed nuclear warheads and 700 deployed missiles and bombers, and envisages sweeping on-site inspections to verify compliance.
The Russian military on Wednesday rolled out a new missile and released its specifications, seeking to dispel the U.S. claim that the weapon violates a key nuclear arms pact.
NATO Secretary-General Jens Stoltenberg is urging Russia to provide details about a new missile system the United States and other allies claim violates an important nuclear weapons treaty.