"We will not engage in a negotiation regarding the further release or dissemination of illegally obtained US government's classified materials," Harold Hongju Koh, the Legal Adviser at the State Department, said in a letter to Jennifer Robinson, Attorney for WikiLeaks founder Julian Assange.
The letter was in response to the communication from WikiLeaks a day earlier in which it informed the US about its intentions to publish classified millions of American government documents.
"Despite your stated desire to protect those lives, you have done the opposite and endangered the lives of countless individuals. You have undermined your stated objective by disseminating this material widely, without redaction, and without regard to the security and sanctity of the lives your actions endanger," Koh said in his letter, which was released to the press late last night.
Ahead of the possible release of the classified documents, the letter said: "As you know, if any of the materials you intend to publish were provided by any government officials, or any intermediary without proper authorisation, they were provided in violation of US law and without regard for the grave consequences of this action.
"As long as WikiLeaks holds such material, the violation of the law is ongoing... It is our understanding from conversations with representatives from 'The New York Times', 'The Guardian' and 'Der Speigel', that WikiLeaks also has provided approximately 250,000 documents to each of them for publication, furthering the illegal dissemination of classified documents."
The State Department said it will not engage in a negotiation regarding the further release or dissemination of the US government classified materials.
"If you are genuinely interested in seeking to stop the damage from your actions, you should: 1) ensure WikiLeaks ceases publishing any and all such materials; 2) ensure WikiLeaks returns any and all classified US Government material in its possession; and 3) remove and destroy all records of this material from WikiLeaks' databases," Koh said.
Publication of documents of this nature at a minimum, the State Department said, would place at risk the lives of countless innocent individuals – from journalists to human rights activists and bloggers to soldiers to individuals providing information to further peace and security.
The publication of classified documents would also place at risk ongoing military operations, including operations to stop terrorists, traffickers in human beings and illicit arms, violent criminal enterprises and other actors that threaten global security, the State Department said.
In his letter, Koh said that the publication of the classified documents would also place at risk ongoing cooperation between countries – partners, allies and common stakeholders – to confront common challenges from terrorism to pandemic diseases to nuclear proliferation that threaten global stability.
"In your (WikiLeaks') letter, you say you want – consistent with your goal of 'maximum disclosure' – information regarding individuals who may be 'at significant risk of harm' because of your actions," he said.
The State Department letter was made public a day after the US reached out to India and other key governments warning them about possible Wikileaks release.
"We do not know precisely what WikiLeaks has or what it plans to do. We have made our position clear. These documents should not be released," State Department Spokesman P J Crowley had said earlier.