"He is not at a greater risk of being handed over from Sweden than from Britain," he told the AP.
Borgstrom wasn't the only one expressing impatience. Ola Lofgren, of the Swedish prosecutor general's office, said it was in everyone's interest that the judicial back-and-forth "is shortened as much as possible."
Australia's government also weighed in, saying in a statement that it would "closely monitor" any proceedings against Assange in Sweden.
Unusually, Assange did not appear in court Wednesday; he was reportedly stuck in traffic. The WikiLeaks chief has spent much of the past 18 months living in a supporter's mansion in rural England.
Although his website has languished amid legal and financial issues, he's moved on to other projects, including a WikiLeaks-themed social networking site and a talk show on the Russian government's English-language broadcaster, RT.
WikiLeaks spokesman Kristinn Hrafnsson said Wednesday's judgment was "disappointing, but not surprising." He noted that Assange's legal options weren't exhausted, although he declined to speak about future strategy.
Karl Ritter and David MacDougall in Stockholm, and Rod McGuirk in Sydney contributed to this report.
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