Mr Assange condemned the court order, saying it amounted to harassment.
"If the Iranian government was to attempt to coercively obtain this information from journalists and activists of foreign nations, human rights groups around the world would speak out," he said in a statement.
Jónsdóttir says on her Facebook page and on Twitter that US authorities have demanded to get all blogs that she has written since November 1 2009. “Don’t they know that I am an MP?” she asks.
In an interview with mbl.is Icelandic Interior Minister Ögmundur Jónasson said that at first sight the case of US authorities against Icelandic MP Birgitta Jónsdóttir seems to be “very odd and grave.”
In spring 2009 Birgitta Jónsdóttir assisted with getting a video of American soldiers shooting at civilians in Bagdad from a helicopter. “It is completely unacceptable that I am considered to be a criminal just because I worked on this video and as a volunteer for Wikileaks. If the United States needs information about me they could contact me directly. The US ambassador could have spoken directly do me.”