Mamelodi Sundowns released a statement earlier in the week which according to Sky Sports: "gave instructions to the management to finalise the deal."
Tau will now be free to undergo a medical examination, and discuss personal terms with the club, however, to play in England, he would need a work permit.
The 24-year-old has been capped 12 times for South Africa, and was named the Footballer of the Year in the Premier Soccer League in 2018, after scoring 11 goals in 30 league appearances.
The player refused to attend preseason training in an attempt to speed up the deal, but the club said in a statement:
"Tau and his agent came to see [the president] and apologised for disclosing confidential information to the media and for Percy Tau not reporting for training."
If the deal goes through it could make Tau the most expensive player from the South African Premier Soccer League.