The English Football League (EFL) has given Reading's owner an ultimatum - either to "fund the club adequately" or "make immediate arrangements to sell", days after protests spilled on to the pitch.
It said owner Dai Yongge was "no longer in a position - or does not have the motivation" to support the club financially.
Dai has been fined a further £50,000 by the league for failing to fund a deposit account to cover the salaries of players and staff, taking the total penalty to £80,000.
Reading are lingering fourth from bottom in League One, following EFL-imposed sanctions, as many fans want the Chinese businessman to sell the club.
He is blamed by many supporters for the club's problems, including wages not being paid and a winding-up order being served in October over unpaid taxes.
The EFL said Reading's staff "have no reassurance" of being paid, and this "demonstrates a clear disregard for his obligations as a director" of the club.
The team's match against Port Vale was abandoned on Saturday after around 1,000 home fans protesting against Dai invaded the pitch of Reading's Select Car Leasing Stadium.
Sell Before we Dai, a fan-led protest group, described it as a "dark day for Reading Football Club", adding the demonstration proved "Reading fans will not be ignored and will fight to the bitter end for our club".
The EFL said the scenes were "unfortunate" adding that "entering the field of play is a criminal offence".
Its board is to discuss the pitch invasion later this week given its responsibility to ensure all 72 clubs that fall under the EFL's three divisions follow the pre-agreed rules.
Reading manager Ruben Selles said he fears the club may be forced to play home games behind closed doors.
Dai took charge in 2017 but has come under criticism after the club was hit with a number of penalties for financial mismanagement, including a four-point deduction this season for a late payment of the monthly wage bill.