The chairman of the Joint Chiefs of Staff said Tuesday he was "appalled" by the leak of military documents that were published in The New York Times and other news outlets, but said it "changes nothing" about the administration's war strategy.

Adm. Mike Mullen, the nation's top military official, condemned the whistleblower website WikiLeaks for releasing classified military documents detailing U.S. intelligence that Pakistan's intelligence service is assisting Afghan insurgents, including the Taliban and al Qaeda.

Mullen tweeted Tuesday:

Appalled by classified docs leak to Wikileaks & decision to post. It changes nothing on Afghanistan strategy or our relationship w/Pakistan

Mullen's comment came minutes after President Obama commented for the first time on the leaks. 

"These documents don't reveal any issues that haven't already informed our public debate on Afghanistan," the president said in the Rose Garden.

The White House has called the leak a "breach of federal law" that could harm national security, and the Pentagon has launched a criminal investigation to find its source.