Forest already had restrictions placed upon them for breaching Financial Fair Play rules but now they have been automatically hit with a blanket ban on signing any players after missing the due date for the latest instalment on their club-record signing Britt Assombalonga, who moved to the City Ground from Peterborough in a £5.5million deal in the summer
Posh chairman Darragh MacAnthony called the situation a "disgrace" on Twitter after his club's attempts to bring in new players ahead of Monday night's transfer deadline were undermined, and the 38-year-old Dubliner wants the Football League to take further action
Missing the payment, thought to be due by January 30, meant Forest were unable to bring anybody in on Monday.
And as things stand, the Reds will be prohibited from adding to their squad when the loan window opens again next week - unless they pay the Sky Bet League One club.
Al-Hasawi has promised that will happen shortly.
"I can assure you any outstanding payments will be resolved imminently and our embargo situation will not change," the Kuwaiti owner said on Twitter.
"To clarify, once our outstanding payments have been resolved we will still be able to sign players on emergency loans under FFP rules."
There have been issues regarding the distribution of money since Al-Hasawi's takeover of the club in the summer of 2012
Forest have been late in paying clubs for players, with Hull and Crystal Palace thought to have been left waiting for payments owed for the Tom Ince and Jack Hunt loan deals
Many agents and club suppliers are also understood to have been paid late - or to still be awaiting money.
Source : PA