"The move comes nearly seven months after Ecuador threatened to remove his protection and summarily cut off his access to the outside world, including by refusing to allow journalists and human rights organisations to see him, and installing three signal jammers in the embassy to prevent his phone calls and internet access", WikiLeaks declared.
A domestic court is set to hear Mr Assange's case next week, when Mr Garzon will explain the embassy's actions WikiLeaks perceived as a violation of its founder's human rights.
It also claims that Ecuador's government has refused to allow Assange to be visited by Human Rights Watch general counsel Dinah PoKempner and has blocked several meetings between him and his lawyers.
The move to start legal proceedings comes just days after Ecuador issued Assange with a list of rules to obey if he wanted to continue living in the embassy.
The whistleblowing website says Assange's access to the outside world has been "summarily cut off", and that Quito has threatened to remove the protection granted to him since being given political asylum.
Failure to abide by the rules would result in the termination of his asylum in the embassy, the Ecuadorian government said, according to the memo, seen by The Guardian newspaper.
Ecuador feared Mr Assange could make more controversial statements that would have strained the country's relationship with the United Kingdom and the European Union.
It also threatened to confiscate Assange's cat if he didn't take better care of its "well-being, food, and hygiene".
Among them, there was the prohibition of using the internet to make political statements and the obligation for Mr Assange to clean his own bathroom.
This new protocol will also be challenged by the WikiLeaks lawyer and branded as a way of "censoring" freedom of opinion, speech and association.
A statement said: "Ecuador's measures against Julian Assange have been widely condemned by the human rights community".
It added that the embassy was requiring Assange's visitors - including journalists and lawyers - to disclose "private or political details such as their social media usernames".