Worcester Warriors will be suspended from all competitions unless they prove to the Rugby Football Union they have a "credible" plan for the future by 17:00 BST on Monday, 26 September.
The RFU also wants to see evidence of insurance cover and funds to cover the monthly payroll by the deadline.
The troubled club has to prove it can safely stage this Saturday's match with Newcastle by 12:00 on Thursday.
Warriors lost their opening home game against Exeter 36-21 last Sunday.
There was serious doubt over whether the match would take place and it was only confirmed 48 hours beforehand after Warriors obtained a safety certificate allowing them to play in front of a reduced capacity, following a similar threat from the RFU.
Many of the club's non-playing staff are still waiting for their full pay for August, having received only 65% of their salaries.
Owners Jason Whittingham and Colin Goldring announced they had "agreed" a deal to sell the financially-troubled club on 13 September, with only the signing-off of the contract holding up completion of the sale.
After Sunday's spirited defeat by the Chiefs, Whittingham and Goldring said they expected the deal to go through within 48 hours - a deadline that passed on Tuesday.
In a statement the RFU said they "remain concerned that the lack of available funds will not allow the club to be sustainable over the long term".
Together with Premiership Rugby and the Department of Culture, Media & Sport (DCMS), the RFU has "been seeking assurances from the Worcester Warriors owners regarding funding and potential new ownership proposals for several weeks".
With the club's insurance cover at Sixways set to run out at midnight on Monday, the governing body has written to Warriors to confirm they will be "suspended from all competitions, including the Gallagher Premiership, Allianz Premier 15s and Allianz Cup if the club cannot evidence insurance cover in place, availability of funds to meet the monthly payroll, and a credible plan to take the club forward, by 5pm on 26 September".
The RFU added it is "grateful" to the club's staff for their "hard work in being able to provide the required information to allow the games to go ahead last weekend and in the week ahead" and have set "set the same conditions for the matches this weekend to go ahead as were in place for the previous weekend.
"These must be met by noon on Thursday, 22 September, as, in particular, Newcastle will be travelling on Friday 23 September."
Warriors have only been able to name a 22-player squad for Wednesday's Premiership Cup match at Gloucester, with a current coach and former player coming out of retirement to help.
Academy backs and transitions coach Jonny Goodridge, 41, and 37-year-old flanker Mat Gilbert, who retired from playing in April, have agreed to be on the bench at Kingsholm, with Gloucester giving tickets to the game to Warriors staff and non-playing players.
Lock Graham Kitchener, who came off the bench in both Worcester's Premiership matches against London Irish and Exeter, is the only player in the squad to have played so far this season.