WikiLeaks drew condemnation from US and Afghan officials after it released its "Afghan War Diary"in July, laying bare classified military documents dealing with the war from 2004 to December 2009.
The group announced last week that it planned to release a second batch of documents within "two weeks to a month" and Assange said that it was these documents that the military had been in contact about.
"This week we received contact through out lawyers" that US military officials "want to discuss the issue", he said on Wednesday.
Assange said that contacts had been brokered by the US Army Criminal Investigation Command (CID).
When asked if CID had made contact with Wikileaks lawyers, Whitman said: "CID is conducting an investigation and I am not going to comment on their investigation".
The release of the classified US military documents has been criticised in some quarters for being done without adequately protecting the names, including those of Afghans working for Nato and the US, contained in the documents.
Reporters Without Borders, a Paris-based media watchdog, has criticised Wikileaks for being "irresponsible" in its release of information.
But Assange said: "We encourage other media and human rights who have a genuine concern about reviewing the material to assist us with the difficult and very expensive task of getting a large historical archive into the public's record."
Assange, an Australian national who spends most of his time in Iceland, is preparing an application for a publishing certificate in Sweden, that would allow Wikileaks to take full advantage of the Scandinavian country's press freedom laws.
However, that also means Wikileaks would have to appoint a publisher that could be held legally responsible for the material.
Wikileaks routes its material through Sweden and Belgium because of the whistleblower protection offered by laws in those countries, but it also has backup servers in other countries to make sure the site is not shut down, Assange said.