In a statement issued Wednesday afternoon, the Executive Office of the President expressed concern over the lack of privacy safeguards in the CISPA bill and said it "strongly opposes" H.R. 3523 as written.

"H.R. 3523 effectively treats domestic cybersecurity as an intelligence activity and thus, significantly departs from longstanding efforts to treat the Internet and cyberspace as civilian spheres," the statement read. If the bill was presented to the President, "his senior advisors would recommend that he veto the bill."

The White House veto threat comes on the eve of a scheduled vote on the bill in the House on Thursday. The threat is not entirely unexpected. Last week, a spokeswoman from the White House National Security Council had already the Executive Office's concerns over it.

Rep. Mike J. Rogers (R-Mich.) and Rep. C.A. Dutch Ruppersberger (D-Md.) introduced CISPA in the U.S. House of Representatives last November.

Backers say the bill aims to improve Internet security by making it easier for Internet Service Providers (ISPs) and Internet companies such as Google and Facebook to collect and share a wide range of threat-related data with government security agencies.