He said a deal ending enrichment "was on the table a hundred years ago" but "has been lost."
The president’s handshake with Cuban President Raúl Castro provoked disapproval from GOP.
Washington's top diplomat in Afghanistan told Congress that President Hamid Karzai is playing a dangerous game in stonewalling a postwar pact, reiterating the Obama administration remains willing to pull all forces out of the country next year.
"Can imagine what Nelson Mandela would say," Leahy tweeted.
McConnell criticized Reid for pushing the Defense authorization bill without amendments.
The leading Cuba hawk in Congress slammed Obama for shaking the Cuban leader's hand.
A bipartisan group of House members has proposed a resolution honoring the life of Nelson Mandela, the anti-apartheid icon and former South African president who died last week.
McCain later said he was joking, although the gesture "was terrible."
Rubio says Obama should have asked Castro about basic freedoms in Cuba.
The chemical weapons watchdog Organization for the Prohibition of Chemical Weapons (OPCW) on Tuesday formally accepted this year’s Nobel Peace Prize.
“This is the first time that the Peace Prize has been awarded to an organization that is actively engaged in disarmament as a practical and ongoing reality,” its director-general Ahmet Uzumcu said in his acceptance speech. “For sixteen years now, the OPCW has been overseeing the elimination of an entire category of weapons of mass destruction. Our task is to consign chemical weapons to history forever.”