The 23-year-old was hospitalised last week and given breathing support after his condition worsened, eventually becoming the first confirmed Ligue 1 player to test positive for COVID-19 after initially testing negative.
"They have stopped assisting Junior's breathing," agent Frederic Guerra told Radio Tele Luxembourg. "It is a long process. He is no longer in a coma. We are, undoubtedly, moving towards good news.
"Junior is starting to breathe by himself so that is already a good thing. The protocol put in place on Friday, which was to wake him up, is ongoing. He is still under surveillance."
Guerra added that Sambia "tested negative and then positive" for coronavirus before praising Montpellier for their "human" handling of such a delicate issue.
"Montpellier are keeping me informed as soon as the doctor has news," he said. "They are also keeping his family informed directly.
"This is a human club. They have really been affected by this and they are sharing the news as and when they have it."
The 2011-12 French champions have not publicly commented on Sambia's condition since Thursday's statement that an unnamed played had been hospitalised.
However, they did take to social media on Saturday to express their gratitude for the messages of support received since the news came to light.
France, like other countries around the globe, has seen football grind to a halt indefinitely because of the outbreak of coronavirus although a June return to action is being targeted.
A return to training in the second week of May with a provisional restart date of mid-June depends on government approval and France moving out of confinement on time.