The 46-year-old Aussie took refuge at the embassy in 2012, when a British judge ruled he should be extradited to Sweden to face sex assault charges. In December, Ecuador even made him a citizen.
Assange has claimed the allegations were politically motivated and could lead to him being extradited to the US to face imprisonment over the publication of secret US materials in 2010.
And now, his tenuous status opens him to arrest by British authorities, who may ship him across the pond to face American justice, several sources told CNN.
Assange's position in the embassy is "in jeopardy," a source familiar with the matter said, and he could either be forced out or choose to leave on his own because he is made to feel very restricted.