The RFU have given Worcester Warriors' owners a deadline of Monday, September 26 to provide proof of funds for payroll, insurance cover and a plan for the future, or else the club will be suspended from all competitions.
The suspension would cover Worcester's participation in the Premiership, Worcester Warriors Women in the Premier 15s, and all involvement in the Allianz Cup.
The financially-strapped club met last Friday's deadline to be allowed to fulfil their home fixture vs Exeter Chiefs by the skin of their teeth but head coach Steve Diamond warned post-match that a line had to be drawn somewhere.
The RFU had previously said it will continue to work with Worcester's owners regarding funding and potential takeover proposals with debts spiralling as high as £25m and many players and staff yet to receive their full August salaries.
They have now given Worcester a firm deadline to meet regarding their future.
"The RFU, Premiership Rugby and DCMS has been seeking assurances from the Worcester Warriors owners regarding funding and potential new ownership proposals for several weeks.
"We are grateful to the staff at Worcester Warriors 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.
"The RFU has 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 Falcons will be travelling on Friday 23 September.
"However, all parties remain concerned that the lack of available funds will not allow the club to be sustainable over the long-term.
"In particular, the RFU is aware that insurance cover is only in place until midnight on Monday 26 September.
"Therefore, the RFU has written to Worcester 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."
Worcester also face a winding-up court hearing on October 6, at which HMRC is expected to demand full payment of a £6m tax bill.
Diamond: I don't know how long we can keep going; Venter: It's mentally tough on playing squad
Diamond said after Sunday's 36-21 defeat to Exeter at Sixways: "I don't know how long we can keep going with this as I've been informed that negotiations are taking place behind the scenes but I'm not party to them.
"In the professional era, no director of rugby should be required to deal with such a situation as the players haven't been paid their August salaries.
"There are limits to how many times players or staff can turn out on goodwill without being paid and it's impossible for anyone to work without any internet and heating with winter around the corner.
"We are hoping to fulfil the fixture with Gloucester on Wednesday. We wanted to bring in a few loan players but at present, we can't afford to pay the RFU the appropriate sum.
"I'm hoping the money we've taken today can be used and not disappear down a black hole as we are on the never-never at the moment.
"Realistically I don't know how long we can keep going for with the winding-up application due in late September, a line has to be drawn somewhere."
Warriors skipper Francois Venter added: "What's going on in the background is mentally tough but hopefully it will get sorted.
"We still don't know the position but it will be very upsetting if it's our last game on this pitch."