Dempsey, Brennan urge Senate to pass cybersecurity legislation

"The administration has repeatedly urged Congress to pass comprehensive cybersecurity legislation to protect the American people from the growing danger of cyberthreats," Brennan said.

Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, told Sen. Jay RockefellerJohn (Jay) Davison RockefellerSenate GOP rejects Trump’s call to go big on gun legislation Overnight Tech: Trump nominates Dem to FCC | Facebook pulls suspected baseball gunman's pages | Uber board member resigns after sexist comment Trump nominates former FCC Dem for another term MORE (D-W.Va.). in a letter that "we must act now" to address the escalating cyberthreats the nation faces. Rockefeller, a co-sponsor of Lieberman's cybersecurity bill, sent Dempsey a letter on Tuesday to ask what action the Senate must take to address the threat of a cyberattack.

"Not only will military systems be targeted by tools that can cause physical destruction, but adversaries will increasingly attempt to hold our nation's core critical infrastructure at risk," Dempsey wrote. "Because the military relies on this infrastructure to defend the nation, we cannot afford to leave our electricity grid and transportation system vulnerable to attack."

Brennan is participating in a phone conference with reporters Wednesday afternoon along with U.S. Cyber Command head Gen. Keith Alexander and other administration officials to discuss cybersecurity legislation.

A cloture vote on Sen. Joe Lieberman's (I-Conn.) Cybersecurity Act is expected on Thursday, but it doesn't appear the measure will receive enough Republican support to move forward. Senate Republicans have voiced concern that Lieberman's measure would saddle companies that operate critical infrastructure with an additional set of regulations to follow.