Blackburn's owners will want definite proof of investment plans before they agree to any takeover of the club.
Rovers chairman John Williams says a number of parties have expressed interest in buying the club, with a company run by wealthy Indian businessman Ahasan Ali Syed confirming a formal approach on Wednesday.
The Jack Walker Trustees will consider selling the club but only if future investment can be guaranteed - Syed is reported to be promising to clear the club's £20million debt and invest £300million to sustain the club over a long period of time.
Syed's investment company Western Gulf Advisory (WGA) made a formal approach to Blackburn's advisers at investment bank Rothschild.
WGA have a non-disclosure agreement about the talks but a company spokeswoman said: "I can confirm that we made a formal approach to buy Blackburn Rovers."
Blackburn chairman John Williams told Press Association Sport: "There have been a number of interested parties for some time and discussions are ongoing."