Kristinn Hrafnsson declined Tuesday to comment on Assange's state of mind prior to the arrest but confirmed he has been in touch with the 39-year-old Australian over the past 24 hours.
He said the arrest will not derail the release of more secret documents.
Hrafnsson told the AP that "this will not change our operation."
But Hrafnsson also said the group had no plans at the moment to release the key to- an "insurance" file that has been distributed to supporters in case of an emergency.
Hrafnsson said that will only come into play if "grave matters" involving Wikileaks staff occur - but did not elaborate on what those would be.
and was due to appear at Westminster Magistrate's Court later in the day.
He had been hiding out at an undisclosed location in Britain since WikiLeaks began publishing U.S. diplomatic cables last week.
CNET reports that WikiLeaks supporters have created mirror sites replicating the site, after Amazon.com stopped hosting the site on its servers and Domain Name System provider EveryDNS.net stopped providing DNS services.
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