The Hong Kong businessman had withdrawn from negotiations last week citing a lack of support for his attempts to take over the club but now hopes to seal a deal within two weeks
Chainrai's company, Portpin, had withdrawn their offer for the League One side last week, citing "zero support" in their efforts to save the club.
That left the Portsmouth Supporters Trust as the only party in negotiations to save Pompey from liquidation, but in a statement Portpin have revealed that problems with that bid led them to return to the table.
"After many discussions with the related parties, including amongst others, the administrator, the Football League, the PFA, and officials from Portsmouth City Council, Portpin Ltd announces that it has decided to take action in order to avoid the imminent liquidation of Portsmouth FC," a Portpin press release read.
"Portpin's offer will be in much the same form as previously with the club's current CVA being honoured and football creditors being settled in accordance with current agreements. Under Football League rules, the satisfactory treatment of football creditor obligations is critical to the financial eco-system of all members of the Football League.
"Although Portpin positively viewed take-over interest by the Portsmouth Supporters Trust (PST), we understood from the Administrator that the terms offered by PST were problematic in two areas.
"The further reduction in football creditor debt to £2 million and the uncertainty of the committed capital raised and held in escrow to both fund the take-over of the business and to provide guarantees for the next three years cash flow.
"We hope to finalise this transaction in the next two weeks.
"Portpin is taking this step to save the club and will look to continue to work with interested parties - including the Portsmouth Supporters Trust - to ensure that the club will have a sound business foundation to enable it to remain financially over the long term.
"We hope everybody including the huge fan base will support this saving process."