Extradition has actually been approved by all relevant UK authorities, after formal reassurance from the US about his treatment. Assange is appealing that decision, arguing then-Home Secretary Priti Patel was an id-- could not seriously accept some meaningless words that they can renege a minute after getting him.
Meanwhile, the Australian government is trying to vaguely save face by making some noise, probably to extract some extra money from Biden to just shut up.