Billiat is in the final year of his three-year deal with the Brazilians after joining from Ajax Cape Town in 2013.
Media reports have suggested that Sundowns have tabled a new deal, but the 25-year-old has yet to commit.
"I have to talk to my manager first. I have to have these discussions with him first before deciding on anything.
"Right now I am just focusing on my game. I am not focused on anything else. So, I will see when we resume what happens.
"I am not worried about my contract. I just want to play good football now until the end of the season."